diff --git a/Занимательное программирование/4/3_recursive/.gitignore b/Занимательное программирование/4/3_recursive/.gitignore
new file mode 100644
index 0000000..bf713c6
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/.gitignore	
@@ -0,0 +1,164 @@
+## Gradle:
+.gradle/
+gradle-app.setting
+/build/
+/android/build/
+/core/build/
+/lwjgl2/build/
+/lwjgl3/build/
+/html/build/
+/teavm/build/
+/ios/build/
+/ios-moe/build/
+/headless/build/
+/server/build/
+/shared/build/
+
+## Java:
+*.class
+*.war
+*.ear
+hs_err_pid*
+.attach_pid*
+
+## Android:
+/android/libs/armeabi-v7a/
+/android/libs/arm64-v8a/
+/android/libs/x86/
+/android/libs/x86_64/
+/android/gen/
+/android/out/
+local.properties
+com_crashlytics_export_strings.xml
+
+## Robovm:
+/ios/robovm-build/
+
+## iOS:
+/ios/xcode/*.xcodeproj/*
+!/ios/xcode/*.xcodeproj/xcshareddata
+!/ios/xcode/*.xcodeproj/project.pbxproj
+/ios/xcode/native/
+/ios/IOSLauncher.app
+/ios/IOSLauncher.app.dSYM
+
+## GWT:
+/html/war/
+/html/gwt-unitCache/
+.apt_generated/
+/html/war/WEB-INF/deploy/
+/html/war/WEB-INF/classes/
+.gwt/
+gwt-unitCache/
+www-test/
+.gwt-tmp/
+
+## TeaVM:
+# Not sure yet...
+
+## IntelliJ, Android Studio:
+.idea/
+*.ipr
+*.iws
+*.iml
+
+## Eclipse:
+.classpath
+.project
+.metadata/
+/android/bin/
+/core/bin/
+/lwjgl2/bin/
+/lwjgl3/bin/
+/html/bin/
+/teavm/bin/
+/ios/bin/
+/ios-moe/bin/
+/headless/bin/
+/server/bin/
+/shared/bin/
+*.tmp
+*.bak
+*.swp
+*~.nib
+.settings/
+.loadpath
+.externalToolBuilders/
+*.launch
+
+
+## NetBeans:
+
+/nbproject/private/
+/android/nbproject/private/
+/core/nbproject/private/
+/lwjgl2/nbproject/private/
+/lwjgl3/nbproject/private/
+/html/nbproject/private/
+/teavm/nbproject/private/
+/ios/nbproject/private/
+/ios-moe/nbproject/private/
+/headless/nbproject/private/
+/server/nbproject/private/
+/shared/nbproject/private/
+
+/nbbuild/
+/android/nbbuild/
+/core/nbbuild/
+/lwjgl2/nbbuild/
+/lwjgl3/nbbuild/
+/html/nbbuild/
+/teavm/nbbuild/
+/ios/nbbuild/
+/ios-moe/nbbuild/
+/headless/nbbuild/
+/server/nbbuild/
+/shared/nbbuild/
+
+/dist/
+/android/dist/
+/core/dist/
+/lwjgl2/dist/
+/lwjgl3/dist/
+/html/dist/
+/teavm/dist/
+/ios/dist/
+/ios-moe/dist/
+/headless/dist/
+/server/dist/
+/shared/dist/
+
+/nbdist/
+/android/nbdist/
+/core/nbdist/
+/lwjgl2/nbdist/
+/lwjgl3/nbdist/
+/html/nbdist/
+/teavm/nbdist/
+/ios/nbdist/
+/ios-moe/nbdist/
+/headless/nbdist/
+/server/nbdist/
+/shared/nbdist/
+
+nbactions.xml
+nb-configuration.xml
+
+## OS-Specific:
+.DS_Store
+Thumbs.db
+
+## Miscellaneous:
+*~
+*.*#
+*#*#
+/.kotlin/
+/assets/assets.txt
+
+## Special cases:
+
+## There is a resource-config.json file generated by nativeimage.gradle if you use Graal Native Image.
+## Some usage may need extra resource configuration in a different file with the same name.
+## You could also add that configuration to the text in nativeimage.gradle .
+## You should delete or comment out the next line if you have configuration in a different resource-config.json .
+**/resource-config.json
diff --git a/Занимательное программирование/4/3_recursive/assets/sample.txt b/Занимательное программирование/4/3_recursive/assets/sample.txt
new file mode 100644
index 0000000..22cb16a
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/assets/sample.txt	
@@ -0,0 +1,21 @@
+5 4
+1 1
+1 1
+1 0
+1 1
+1 0
+0 1
+1 0
+0 1
+0 0
+1 1
+0 1
+1 0
+1 0
+0 0
+0 0
+1 1
+0 0
+0 1
+0 1
+0 1
diff --git a/Занимательное программирование/4/3_recursive/build.gradle b/Занимательное программирование/4/3_recursive/build.gradle
new file mode 100644
index 0000000..227467c
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/build.gradle	
@@ -0,0 +1,148 @@
+buildscript {
+}
+plugins {
+  id "application"
+}
+apply plugin: 'java-library'
+
+// From https://lyze.dev/2021/04/29/libGDX-Internal-Assets-List/
+// The article can be helpful when using assets.txt in your project.
+tasks.register('generateAssetList') {
+  inputs.dir("${project.rootDir}/assets/")
+  // projectFolder/assets
+  File assetsFolder = new File("${project.rootDir}/assets/")
+  // projectFolder/assets/assets.txt
+  File assetsFile = new File(assetsFolder, "assets.txt")
+  // delete that file in case we've already created it
+  assetsFile.delete()
+
+  // iterate through all files inside that folder
+  // convert it to a relative path
+  // and append it to the file assets.txt
+  fileTree(assetsFolder).collect { assetsFolder.relativePath(it) }.sort().each {
+    assetsFile.append(it + "\n")
+  }
+}
+processResources.dependsOn 'generateAssetList'
+
+compileJava {
+  options.incremental = true
+}
+
+version = "$projectVersion"
+ext.appName = 'Labyrinth'
+repositories {
+  mavenCentral()
+  // You may want to remove the following line if you have errors downloading dependencies.
+  mavenLocal()
+  maven { url = 'https://central.sonatype.com/repository/maven-snapshots/' }
+  maven { url = 'https://jitpack.io' }
+}
+
+[compileJava, compileTestJava]*.options*.encoding = 'UTF-8'
+
+sourceSets.main.resources.srcDirs += [ rootProject.file('assets').path ]
+application.mainClass = 'net.caraus.labyrinth.lwjgl3.Lwjgl3Launcher'
+
+java.sourceCompatibility = 17
+java.targetCompatibility = 21
+if (JavaVersion.current().isJava9Compatible()) {
+        compileJava.options.release.set(17)
+}
+
+dependencies {
+  api "com.badlogicgames.gdx:gdx:$gdxVersion"
+  implementation "com.badlogicgames.gdx:gdx-backend-lwjgl3:$gdxVersion"
+  implementation "com.badlogicgames.gdx:gdx-lwjgl3-angle:$gdxVersion"
+  implementation "com.badlogicgames.gdx:gdx-platform:$gdxVersion:natives-desktop"
+}
+
+def os = System.properties['os.name'].toLowerCase(Locale.ROOT)
+
+run {
+  workingDir = rootProject.file('assets').path
+
+  if (os.contains('mac')) jvmArgs += "-XstartOnFirstThread"
+}
+
+jar {
+  // sets the name of the .jar file this produces to the name of the game or app, with the version after.
+  archiveFileName.set("${appName}-${projectVersion}.jar")
+  // the duplicatesStrategy matters starting in Gradle 7.0; this setting works.
+  duplicatesStrategy = DuplicatesStrategy.EXCLUDE
+  dependsOn configurations.runtimeClasspath
+  from { configurations.runtimeClasspath.collect { it.isDirectory() ? it : zipTree(it) } }
+  // these "exclude" lines remove some unnecessary duplicate files in the output JAR.
+  exclude('META-INF/INDEX.LIST', 'META-INF/*.SF', 'META-INF/*.DSA', 'META-INF/*.RSA')
+  dependencies {
+    exclude('META-INF/INDEX.LIST', 'META-INF/maven/**')
+  }
+  // setting the manifest makes the JAR runnable.
+  // enabling native access helps avoid a warning when Java 24 or later runs the JAR.
+  manifest {
+    attributes 'Main-Class': application.mainClass, 'Enable-Native-Access': 'ALL-UNNAMED'
+  }
+  // this last step may help on some OSes that need extra instruction to make runnable JARs.
+  doLast {
+    file(archiveFile).setExecutable(true, false)
+  }
+}
+
+// Builds a JAR that only includes the files needed to run on macOS, not Windows or Linux.
+// The file size for a Mac-only JAR is about 7MB smaller than a cross-platform JAR.
+tasks.register("jarMac") {
+  dependsOn("jar")
+  group("build")
+  jar.archiveFileName.set("${appName}-${projectVersion}-mac.jar")
+  jar.exclude("windows/x86/**", "windows/x64/**", "linux/arm32/**", "linux/arm64/**", "linux/x64/**", "**/*.dll", "**/*.so",
+    'META-INF/INDEX.LIST', 'META-INF/*.SF', 'META-INF/*.DSA', 'META-INF/*.RSA')
+  dependencies {
+    jar.exclude("windows/x86/**", "windows/x64/**", "linux/arm32/**", "linux/arm64/**", "linux/x64/**",
+      'META-INF/INDEX.LIST', 'META-INF/maven/**')
+  }
+}
+
+// Builds a JAR that only includes the files needed to run on Linux, not Windows or macOS.
+// The file size for a Linux-only JAR is about 5MB smaller than a cross-platform JAR.
+tasks.register("jarLinux") {
+  dependsOn("jar")
+  group("build")
+  jar.archiveFileName.set("${appName}-${projectVersion}-linux.jar")
+  jar.exclude("windows/x86/**", "windows/x64/**", "macos/arm64/**", "macos/x64/**", "**/*.dll", "**/*.dylib",
+    'META-INF/INDEX.LIST', 'META-INF/*.SF', 'META-INF/*.DSA', 'META-INF/*.RSA')
+  dependencies {
+    jar.exclude("windows/x86/**", "windows/x64/**", "macos/arm64/**", "macos/x64/**",
+      'META-INF/INDEX.LIST', 'META-INF/maven/**')
+  }
+}
+
+// Builds a JAR that only includes the files needed to run on Windows, not Linux or macOS.
+// The file size for a Windows-only JAR is about 6MB smaller than a cross-platform JAR.
+tasks.register("jarWin") {
+  dependsOn("jar")
+  group("build")
+  jar.archiveFileName.set("${appName}-${projectVersion}-win.jar")
+  jar.exclude("macos/arm64/**", "macos/x64/**", "linux/arm32/**", "linux/arm64/**", "linux/x64/**", "**/*.dylib", "**/*.so",
+    'META-INF/INDEX.LIST', 'META-INF/*.SF', 'META-INF/*.DSA', 'META-INF/*.RSA')
+  dependencies {
+    jar.exclude("macos/arm64/**", "macos/x64/**", "linux/arm32/**", "linux/arm64/**", "linux/x64/**",
+      'META-INF/INDEX.LIST', 'META-INF/maven/**')
+  }
+}
+
+distributions {
+  main {
+    contents {
+      into('libs') {
+        project.configurations.runtimeClasspath.files.findAll { file ->
+          file.getName() != project.tasks.jar.outputs.files.singleFile.name
+        }.each { file ->
+          exclude file.name
+        }
+      }
+    }
+  }
+}
+
+startScripts.dependsOn(':lwjgl3:jar')
+startScripts.classpath = project.tasks.jar.outputs.files
diff --git a/Занимательное программирование/4/3_recursive/gradle.properties b/Занимательное программирование/4/3_recursive/gradle.properties
new file mode 100644
index 0000000..4f843c4
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/gradle.properties	
@@ -0,0 +1,19 @@
+# This doesn't need to be false, and some projects may be able to take advantage of setting daemon to true.
+# We set it to false by default in order to avoid too many daemons from being created and persisting; each needs RAM.
+org.gradle.daemon=false
+# Sets starting memory usage to 512MB, maximum memory usage to 1GB, and tries to set as much to use Unicode as we can.
+org.gradle.jvmargs=-Xms512M -Xmx1G -Dfile.encoding=UTF-8 -Dconsole.encoding=UTF-8
+# "Configure on-demand" must be false because it breaks projects that have Android modules. The default is also false.
+org.gradle.configureondemand=false
+# The logging level determines which messages get shown about how Gradle itself is working, such as if build.gradle
+# files are fully future-proof (which they never are, because Gradle constantly deprecates working APIs).
+# You can change 'quiet' below to 'lifecycle' to use Gradle's default behavior, which shows some confusing messages.
+# You could instead change 'quiet' below to 'info' to see info that's important mainly while debugging build files.
+# Note that if you want to use Gradle Build Scans, you should set the below logging level to 'lifecycle', otherwise
+# the link to the scan won't get shown at all.
+# Documented at: https://docs.gradle.org/current/userguide/command_line_interface.html#sec:command_line_logging
+org.gradle.logging.level=quiet
+enableGraalNative=false
+graalHelperVersion=2.0.1
+gdxVersion=1.14.0
+projectVersion=1.0.0
diff --git a/Занимательное программирование/4/3_recursive/gradle/gradle-daemon-jvm.properties b/Занимательное программирование/4/3_recursive/gradle/gradle-daemon-jvm.properties
new file mode 100644
index 0000000..67ed422
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/gradle/gradle-daemon-jvm.properties	
@@ -0,0 +1,12 @@
+#This file is generated by updateDaemonJvm
+toolchainUrl.FREE_BSD.AARCH64=https\://api.foojay.io/disco/v3.0/ids/73c462e34475aeb6509ab7ba3eda218f/redirect
+toolchainUrl.FREE_BSD.X86_64=https\://api.foojay.io/disco/v3.0/ids/54001d0b636ad500b432d20ef3d580d0/redirect
+toolchainUrl.LINUX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/73c462e34475aeb6509ab7ba3eda218f/redirect
+toolchainUrl.LINUX.X86_64=https\://api.foojay.io/disco/v3.0/ids/54001d0b636ad500b432d20ef3d580d0/redirect
+toolchainUrl.MAC_OS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/29c55e6bad8a0049163f0184625cecd9/redirect
+toolchainUrl.MAC_OS.X86_64=https\://api.foojay.io/disco/v3.0/ids/3ac7a5361c25c0b23d933f44bdb0abd9/redirect
+toolchainUrl.UNIX.AARCH64=https\://api.foojay.io/disco/v3.0/ids/73c462e34475aeb6509ab7ba3eda218f/redirect
+toolchainUrl.UNIX.X86_64=https\://api.foojay.io/disco/v3.0/ids/54001d0b636ad500b432d20ef3d580d0/redirect
+toolchainUrl.WINDOWS.AARCH64=https\://api.foojay.io/disco/v3.0/ids/28937bb8a7f83f57de92429a9a11c04e/redirect
+toolchainUrl.WINDOWS.X86_64=https\://api.foojay.io/disco/v3.0/ids/52fa104f4f641439587f75dd68b31bc2/redirect
+toolchainVersion=17
diff --git a/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.jar b/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..f8e1ee3
Binary files /dev/null and b/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.properties b/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..23449a2
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/gradle/wrapper/gradle-wrapper.properties	
@@ -0,0 +1,7 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-9.2.1-bin.zip
+networkTimeout=10000
+validateDistributionUrl=true
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
diff --git a/Занимательное программирование/4/3_recursive/gradlew b/Занимательное программирование/4/3_recursive/gradlew
new file mode 100755
index 0000000..adff685
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/gradlew	
@@ -0,0 +1,248 @@
+#!/bin/sh
+
+#
+# Copyright © 2015 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+# SPDX-License-Identifier: Apache-2.0
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/HEAD/platforms/jvm/plugins-application/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+# This is normally unused
+# shellcheck disable=SC2034
+APP_BASE_NAME=${0##*/}
+# Discard cd standard output in case $CDPATH is set (https://github.com/gradle/gradle/issues/25036)
+APP_HOME=$( cd -P "${APP_HOME:-./}" > /dev/null && printf '%s\n' "$PWD" ) || exit
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    if ! command -v java >/dev/null 2>&1
+    then
+        die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        # In POSIX sh, ulimit -H is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        # In POSIX sh, ulimit -n is undefined. That's why the result is checked to see if it worked.
+        # shellcheck disable=SC2039,SC3045
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Collect all arguments for the java command:
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and optsEnvironmentVar are not allowed to contain shell fragments,
+#     and any embedded shellness will be escaped.
+#   * For example: A user cannot expect ${Hostname} to be expanded, as it is an environment variable and will be
+#     treated as '${Hostname}' itself on the command line.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -jar "$APP_HOME/gradle/wrapper/gradle-wrapper.jar" \
+        "$@"
+
+# Stop when "xargs" is not available.
+if ! command -v xargs >/dev/null 2>&1
+then
+    die "xargs is not available"
+fi
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"
diff --git a/Занимательное программирование/4/3_recursive/gradlew.bat b/Занимательное программирование/4/3_recursive/gradlew.bat
new file mode 100755
index 0000000..e509b2d
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/gradlew.bat	
@@ -0,0 +1,93 @@
+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+@rem SPDX-License-Identifier: Apache-2.0
+@rem
+
+@if "%DEBUG%"=="" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%"=="" set DIRNAME=.
+@rem This is normally unused
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if %ERRORLEVEL% equ 0 goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH. 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo. 1>&2
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME% 1>&2
+echo. 1>&2
+echo Please set the JAVA_HOME variable in your environment to match the 1>&2
+echo location of your Java installation. 1>&2
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -jar "%APP_HOME%\gradle\wrapper\gradle-wrapper.jar" %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if %ERRORLEVEL% equ 0 goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+set EXIT_CODE=%ERRORLEVEL%
+if %EXIT_CODE% equ 0 set EXIT_CODE=1
+if not ""=="%GRADLE_EXIT_CONSOLE%" exit %EXIT_CODE%
+exit /b %EXIT_CODE%
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/Занимательное программирование/4/3_recursive/icons/logo.icns b/Занимательное программирование/4/3_recursive/icons/logo.icns
new file mode 100644
index 0000000..5e41ad7
Binary files /dev/null and b/Занимательное программирование/4/3_recursive/icons/logo.icns differ
diff --git a/Занимательное программирование/4/3_recursive/icons/logo.ico b/Занимательное программирование/4/3_recursive/icons/logo.ico
new file mode 100644
index 0000000..c4f2d5e
Binary files /dev/null and b/Занимательное программирование/4/3_recursive/icons/logo.ico differ
diff --git a/Занимательное программирование/4/3_recursive/icons/logo.png b/Занимательное программирование/4/3_recursive/icons/logo.png
new file mode 100644
index 0000000..f810616
Binary files /dev/null and b/Занимательное программирование/4/3_recursive/icons/logo.png differ
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Location.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Location.java
new file mode 100644
index 0000000..b2f5a46
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Location.java	
@@ -0,0 +1,8 @@
+package net.caraus.labyrinth;
+
+public record Location(boolean leftWall, boolean upWall) {
+    @Override
+    public String toString() {
+        return String.format("(%s, %s)", leftWall, upWall);
+    }
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Main.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Main.java
new file mode 100644
index 0000000..2ef6adc
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Main.java	
@@ -0,0 +1,62 @@
+package net.caraus.labyrinth;
+
+import com.badlogic.gdx.ApplicationAdapter;
+import com.badlogic.gdx.Gdx;
+import com.badlogic.gdx.files.FileHandle;
+import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
+import com.badlogic.gdx.graphics.Color;
+import static com.badlogic.gdx.graphics.glutils.ShapeRenderer.ShapeType;
+import com.badlogic.gdx.utils.ScreenUtils;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+
+/** {@link com.badlogic.gdx.ApplicationListener} implementation shared by all platforms. */
+public class Main extends ApplicationAdapter {
+    private ShapeRenderer shape;
+    private Maze maze;
+    private RecursiveSolve solver;
+
+    @Override
+    public void create() {
+        shape = new ShapeRenderer();
+
+        FileHandle file = Gdx.files.internal("sample.txt");
+
+        try {
+            this.maze = new Maze(file.reader("utf-8"));
+        } catch (IOException e) {
+        }
+        this.solver = new RecursiveSolve(this.maze, new Point(0, 0), new Point(this.maze.width() - 1, 0));
+        this.solver.start();
+    }
+
+    @Override
+    public void render() {
+        ScreenUtils.clear(0.15f, 0.15f, 0.2f, 1f);
+
+        this.shape.begin(ShapeType.Line);
+
+        this.shape.setColor(Color.RED);
+        this.maze.draw(this.shape);
+
+        this.shape.setColor(Color.GREEN);
+        this.solver.draw(this.shape);
+
+        /* this.elapsedTime += Gdx.graphics.getDeltaTime();
+        if (this.elapsedTime > 1.0f) {
+            if (this.solver.solve() != Solution.CONTINUE) {
+                this.elapsedTime = Float.NEGATIVE_INFINITY;
+            } else {
+                this.elapsedTime -= 1.0f;
+            }
+        } */
+
+        this.shape.end();
+    }
+
+    @Override
+    public void dispose() {
+        this.shape.dispose();
+    }
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Maze.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Maze.java
new file mode 100644
index 0000000..eaeb72b
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Maze.java	
@@ -0,0 +1,84 @@
+package net.caraus.labyrinth;
+
+import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
+import com.badlogic.gdx.math.Vector2;
+
+import java.io.BufferedReader;
+import java.io.Reader;
+import java.io.IOException;
+
+public final class Maze {
+    private Location[][] maze;
+
+    public static final int[] DX = {1, 0, -1, 0};
+    public static final int[] DY = {0, -1, 0, 1};
+    public static final float CELL_SIZE = 75.0f;
+
+    public Maze(Reader inputReader) throws IOException {
+        BufferedReader reader = new BufferedReader(inputReader);
+
+        String[] inputPair = reader.readLine().split(" ");
+        var width = Integer.parseInt(inputPair[0]);
+        var height = Integer.parseInt(inputPair[1]);
+
+        this.maze = new Location[width + 1][height + 1];
+
+        for (var y = 0; y <= height; ++y) {
+            for (var x = 0; x <= width; ++x) {
+                if (y == height || x == width) {
+                    this.maze[x][y] = new Location(true, true);
+                } else {
+                    inputPair = reader.readLine().split(" ");
+                    this.maze[x][y] = new Location(inputPair[1].equals("1"), inputPair[0].equals("1"));
+                }
+            }
+        }
+    }
+
+    public int width() {
+        return this.maze == null ? 0 : this.maze.length - 1;
+    }
+
+    public int height() {
+        return this.maze == null ? 0 : this.maze[0].length - 1;
+    }
+
+    public void draw(ShapeRenderer shape) {
+        for (var x = 0; x < width(); ++x) {
+            for (var y = 0; y < height(); ++y) {
+                var start = new Vector2((x + 1) * CELL_SIZE, (height() - y + 1) * CELL_SIZE);
+
+                if (this.maze[x][y].upWall()) {
+                    var end = new Vector2(start).add(CELL_SIZE, 0);
+
+                    shape.line(start, end);
+                }
+                if (this.maze[x][y].leftWall()) {
+                    var end = new Vector2(start).sub(0, CELL_SIZE);
+
+                    shape.line(start, end);
+                }
+            }
+        }
+        // Рисуем нижнюю и правую стены.
+        var edge = new Vector2(CELL_SIZE * (width() + 1), CELL_SIZE);
+        shape.line(new Vector2(CELL_SIZE, CELL_SIZE), edge);
+        shape.line(new Vector2(edge).add(0, height() * CELL_SIZE), edge);
+    }
+
+    public boolean canGo(Point xy, int deltaIndex) {
+        if (DX[deltaIndex] == -1) {
+            return !this.maze[xy.x()][xy.y()].leftWall();
+        } else if (DX[deltaIndex] == 1) {
+            return !this.maze[xy.x() + 1][xy.y()].leftWall();
+        } else if (DY[deltaIndex] == -1) {
+            return !this.maze[xy.x()][xy.y()].upWall();
+        } else {
+            return !this.maze[xy.x()][xy.y() + 1].upWall();
+        }
+    }
+
+    public Location at(Point xy) {
+        return this.maze[xy.x()][xy.y()];
+    }
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Point.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Point.java
new file mode 100644
index 0000000..6f70d4c
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/Point.java	
@@ -0,0 +1,4 @@
+package net.caraus.labyrinth;
+
+public record Point(int x, int y) {
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/RecursiveSolve.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/RecursiveSolve.java
new file mode 100644
index 0000000..73a2f25
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/RecursiveSolve.java	
@@ -0,0 +1,81 @@
+package net.caraus.labyrinth;
+
+import com.badlogic.gdx.graphics.glutils.ShapeRenderer;
+import java.util.ArrayList;
+import java.util.HashSet;
+
+public final class RecursiveSolve extends Thread {
+    private Maze maze;
+    private Point start;
+    private Point finish;
+    private boolean[][] visited;
+
+    // Результирующий маршрут.
+    private ArrayList<Point> path;
+
+    public RecursiveSolve(Maze maze, Point start, Point finish) {
+        this.maze = maze;
+        this.start = start;
+        this.finish = finish;
+
+        this.visited = new boolean[this.maze.width()][this.maze.height()];
+        this.path = new ArrayList<>(this.maze.width() * this.maze.height() + 1);
+
+        for (var column: this.visited) {
+            for (var y = 0; y < column.length; ++y) {
+                column[y] = false;
+            }
+        }
+    }
+
+    private boolean solve(Point nLocation) throws InterruptedException {
+        this.visited[nLocation.x()][nLocation.y()] = true; // Пометить локацию как посещенную.
+        synchronized(this) {
+            this.path.add(nLocation); // Добавить ее в описание маршрута.
+        }
+        Thread.sleep(500);
+
+        // Если финишная локация найдена, конец алгоритма.
+        if (this.finish.equals(nLocation)) {
+            return true;
+        }
+        for (var i = 0; i < 4; ++i) {
+            // Если дорожка свободна, идем по ней.
+            var neighbour = new Point(nLocation.x() + Maze.DX[i], nLocation.y() + Maze.DY[i]);
+
+            if (maze.canGo(nLocation, i) && !this.visited[neighbour.x()][neighbour.y()]) {
+                // Если решение найдено, конец алгоритма.
+                if (solve(neighbour)) {
+                    return true;
+                }
+            }
+        }
+        synchronized(this) {
+            this.path.remove(this.path.size() - 1);
+        }
+        return false;
+    }
+
+    @Override
+    public void run() {
+        try {
+            solve(this.start);
+        } catch (InterruptedException e) {
+        }
+    }
+
+    private void drawPoint(ShapeRenderer shape, Point nLocation) {
+        final float markSize = 20.0f;
+        final float halfMark = Maze.CELL_SIZE / 2 - markSize / 2;
+
+        shape.ellipse((nLocation.x() + 1) * Maze.CELL_SIZE + halfMark,
+                (this.maze.height() - nLocation.y()) * Maze.CELL_SIZE + halfMark,
+                markSize, markSize);
+    }
+
+    synchronized public void draw(ShapeRenderer shape) {
+        for (var point: this.path) {
+            drawPoint(shape, point);
+        }
+    }
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/Lwjgl3Launcher.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/Lwjgl3Launcher.java
new file mode 100644
index 0000000..d17ac8a
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/Lwjgl3Launcher.java	
@@ -0,0 +1,45 @@
+package net.caraus.labyrinth.lwjgl3;
+
+import com.badlogic.gdx.backends.lwjgl3.Lwjgl3Application;
+import com.badlogic.gdx.backends.lwjgl3.Lwjgl3ApplicationConfiguration;
+import net.caraus.labyrinth.Main;
+
+/** Launches the desktop (LWJGL3) application. */
+public class Lwjgl3Launcher {
+    public static void main(String[] args) {
+        if (StartupHelper.startNewJvmIfRequired()) return; // This handles macOS support and helps on Windows.
+        createApplication();
+    }
+
+    private static Lwjgl3Application createApplication() {
+        return new Lwjgl3Application(new Main(), getDefaultConfiguration());
+    }
+
+    private static Lwjgl3ApplicationConfiguration getDefaultConfiguration() {
+        Lwjgl3ApplicationConfiguration configuration = new Lwjgl3ApplicationConfiguration();
+        configuration.setTitle("Labyrinth");
+        //// Vsync limits the frames per second to what your hardware can display, and helps eliminate
+        //// screen tearing. This setting doesn't always work on Linux, so the line after is a safeguard.
+        configuration.useVsync(true);
+        //// Limits FPS to the refresh rate of the currently active monitor, plus 1 to try to match fractional
+        //// refresh rates. The Vsync setting above should limit the actual FPS to match the monitor.
+        configuration.setForegroundFPS(Lwjgl3ApplicationConfiguration.getDisplayMode().refreshRate + 1);
+        //// If you remove the above line and set Vsync to false, you can get unlimited FPS, which can be
+        //// useful for testing performance, but can also be very stressful to some hardware.
+        //// You may also need to configure GPU drivers to fully disable Vsync; this can cause screen tearing.
+
+        configuration.setWindowedMode(640, 480);
+        //// You can change these files; they are in lwjgl3/src/main/resources/ .
+        //// They can also be loaded from the root of assets/ .
+        configuration.setWindowIcon("libgdx128.png", "libgdx64.png", "libgdx32.png", "libgdx16.png");
+
+        //// This should improve compatibility with Windows machines with buggy OpenGL drivers, Macs
+        //// with Apple Silicon that have to emulate compatibility with OpenGL anyway, and more.
+        //// This uses the dependency `com.badlogicgames.gdx:gdx-lwjgl3-angle` to function.
+        //// You can choose to remove the following line and the mentioned dependency if you want; they
+        //// are not intended for games that use GL30 (which is compatibility with OpenGL ES 3.0).
+        configuration.setOpenGLEmulation(Lwjgl3ApplicationConfiguration.GLEmulation.ANGLE_GLES20, 0, 0);
+
+        return configuration;
+    }
+}
diff --git a/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/StartupHelper.java b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/StartupHelper.java
new file mode 100644
index 0000000..b62cf6f
--- /dev/null
+++ b/Занимательное программирование/4/3_recursive/src/main/java/net/caraus/labyrinth/lwjgl3/StartupHelper.java	
@@ -0,0 +1,204 @@
+/*
+ * Copyright 2020 damios
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+//Note, the above license and copyright applies to this file only.
+
+package net.caraus.labyrinth.lwjgl3;
+
+import com.badlogic.gdx.Version;
+import com.badlogic.gdx.backends.lwjgl3.Lwjgl3NativesLoader;
+import org.lwjgl.system.macosx.LibC;
+import org.lwjgl.system.macosx.ObjCRuntime;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.InputStreamReader;
+import java.lang.management.ManagementFactory;
+import java.util.ArrayList;
+
+import static org.lwjgl.system.JNI.invokePPP;
+import static org.lwjgl.system.JNI.invokePPZ;
+import static org.lwjgl.system.macosx.ObjCRuntime.objc_getClass;
+import static org.lwjgl.system.macosx.ObjCRuntime.sel_getUid;
+
+/**
+ * Adds some utilities to ensure that the JVM was started with the
+ * {@code -XstartOnFirstThread} argument, which is required on macOS for LWJGL 3
+ * to function. Also helps on Windows when users have names with characters from
+ * outside the Latin alphabet, a common cause of startup crashes.
+ * <br>
+ * <a href="https://jvm-gaming.org/t/starting-jvm-on-mac-with-xstartonfirstthread-programmatically/57547">Based on this java-gaming.org post by kappa</a>
+ * @author damios
+ */
+public class StartupHelper {
+
+    private static final String JVM_RESTARTED_ARG = "jvmIsRestarted";
+
+    private StartupHelper() {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * Starts a new JVM if the application was started on macOS without the
+     * {@code -XstartOnFirstThread} argument. This also includes some code for
+     * Windows, for the case where the user's home directory includes certain
+     * non-Latin-alphabet characters (without this code, most LWJGL3 apps fail
+     * immediately for those users). Returns whether a new JVM was started and
+     * thus no code should be executed.
+     * <p>
+     * <u>Usage:</u>
+     *
+     * <pre><code>
+     * public static void main(String... args) {
+     * 	if (StartupHelper.startNewJvmIfRequired(true)) return; // This handles macOS support and helps on Windows.
+     * 	// after this is the actual main method code
+     * }
+     * </code></pre>
+     *
+     * @param redirectOutput
+     *            whether the output of the new JVM should be rerouted to the
+     *            old JVM, so it can be accessed in the same place; keeps the
+     *            old JVM running if enabled
+     * @return whether a new JVM was started and thus no code should be executed
+     *         in this one
+     */
+    public static boolean startNewJvmIfRequired(boolean redirectOutput) {
+        String osName = System.getProperty("os.name").toLowerCase(java.util.Locale.ROOT);
+        if (!osName.contains("mac")) {
+            if (osName.contains("windows")) {
+// Here, we are trying to work around an issue with how LWJGL3 loads its extracted .dll files.
+// By default, LWJGL3 extracts to the directory specified by "java.io.tmpdir", which is usually the user's home.
+// If the user's name has non-ASCII (or some non-alphanumeric) characters in it, that would fail.
+// By extracting to the relevant "ProgramData" folder, which is usually "C:\ProgramData", we avoid this.
+// We also temporarily change the "user.name" property to one without any chars that would be invalid.
+// We revert our changes immediately after loading LWJGL3 natives.
+                String programData = System.getenv("ProgramData");
+                if(programData == null) programData = "C:\\Temp\\"; // if ProgramData isn't set, try some fallback.
+                String prevTmpDir = System.getProperty("java.io.tmpdir", programData);
+                String prevUser = System.getProperty("user.name", "libGDX_User");
+                System.setProperty("java.io.tmpdir", programData + "/libGDX-temp");
+                System.setProperty("user.name", ("User_" + prevUser.hashCode() + "_GDX" + Version.VERSION).replace('.', '_'));
+                Lwjgl3NativesLoader.load();
+                System.setProperty("java.io.tmpdir", prevTmpDir);
+                System.setProperty("user.name", prevUser);
+            }
+            return false;
+        }
+
+        // There is no need for -XstartOnFirstThread on Graal native image
+        if (!System.getProperty("org.graalvm.nativeimage.imagecode", "").isEmpty()) {
+            return false;
+        }
+
+        // Checks if we are already on the main thread, such as from running via Construo.
+        long objc_msgSend = ObjCRuntime.getLibrary().getFunctionAddress("objc_msgSend");
+        long NSThread      = objc_getClass("NSThread");
+        long currentThread = invokePPP(NSThread, sel_getUid("currentThread"), objc_msgSend);
+        boolean isMainThread = invokePPZ(currentThread, sel_getUid("isMainThread"), objc_msgSend);
+        if(isMainThread) return false;
+
+        long pid = LibC.getpid();
+
+        // check whether -XstartOnFirstThread is enabled
+        if ("1".equals(System.getenv("JAVA_STARTED_ON_FIRST_THREAD_" + pid))) {
+            return false;
+        }
+
+        // check whether the JVM was previously restarted
+        // avoids looping, but most certainly leads to a crash
+        if ("true".equals(System.getProperty(JVM_RESTARTED_ARG))) {
+            System.err.println(
+                    "There was a problem evaluating whether the JVM was started with the -XstartOnFirstThread argument.");
+            return false;
+        }
+
+        // Restart the JVM with -XstartOnFirstThread
+        ArrayList<String> jvmArgs = new ArrayList<>();
+        String separator = System.getProperty("file.separator", "/");
+        // The following line is used assuming you target Java 8, the minimum for LWJGL3.
+        String javaExecPath = System.getProperty("java.home") + separator + "bin" + separator + "java";
+        // If targeting Java 9 or higher, you could use the following instead of the above line:
+        //String javaExecPath = ProcessHandle.current().info().command().orElseThrow();
+
+        if (!(new File(javaExecPath)).exists()) {
+            System.err.println(
+                    "A Java installation could not be found. If you are distributing this app with a bundled JRE, be sure to set the -XstartOnFirstThread argument manually!");
+            return false;
+        }
+
+        jvmArgs.add(javaExecPath);
+        jvmArgs.add("-XstartOnFirstThread");
+        jvmArgs.add("-D" + JVM_RESTARTED_ARG + "=true");
+        jvmArgs.addAll(ManagementFactory.getRuntimeMXBean().getInputArguments());
+        jvmArgs.add("-cp");
+        jvmArgs.add(System.getProperty("java.class.path"));
+        String mainClass = System.getenv("JAVA_MAIN_CLASS_" + pid);
+        if (mainClass == null) {
+            StackTraceElement[] trace = Thread.currentThread().getStackTrace();
+            if (trace.length > 0) {
+                mainClass = trace[trace.length - 1].getClassName();
+            } else {
+                System.err.println("The main class could not be determined.");
+                return false;
+            }
+        }
+        jvmArgs.add(mainClass);
+
+        try {
+            if (!redirectOutput) {
+                ProcessBuilder processBuilder = new ProcessBuilder(jvmArgs);
+                processBuilder.start();
+            } else {
+                Process process = (new ProcessBuilder(jvmArgs))
+                        .redirectErrorStream(true).start();
+                BufferedReader processOutput = new BufferedReader(
+                        new InputStreamReader(process.getInputStream()));
+                String line;
+
+                while ((line = processOutput.readLine()) != null) {
+                    System.out.println(line);
+                }
+
+                process.waitFor();
+            }
+        } catch (Exception e) {
+            System.err.println("There was a problem restarting the JVM");
+            e.printStackTrace();
+        }
+
+        return true;
+    }
+
+    /**
+     * Starts a new JVM if the application was started on macOS without the
+     * {@code -XstartOnFirstThread} argument. Returns whether a new JVM was
+     * started and thus no code should be executed. Redirects the output of the
+     * new JVM to the old one.
+     * <p>
+     * <u>Usage:</u>
+     *
+     * <pre>
+     * public static void main(String... args) {
+     * 	if (StartupHelper.startNewJvmIfRequired()) return; // This handles macOS support and helps on Windows.
+     * 	// the actual main method code
+     * }
+     * </pre>
+     *
+     * @return whether a new JVM was started and thus no code should be executed
+     *         in this one
+     */
+    public static boolean startNewJvmIfRequired() {
+        return startNewJvmIfRequired(true);
+    }
+}
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