Добавлена третья задача пятой главы

Занимательное программирование/5/3_context/context.cpp

@@ -0,0 +1,67 @@
+#include "utf8.h"
+#include "context.hpp"
+
+context_occurrence::context_occurrence(utf8::utfchar32_t character)
+{
+    this->counts.insert({ character, 1 });
+}
+
+void context_occurrence::add(utf8::utfchar32_t character)
+{
+    ++this->count;
+
+    auto lookup_result = this->counts.find(character);
+    if (lookup_result == this->counts.end())
+    {
+        this->counts.insert({ character, 1 });
+    }
+    else
+    {
+        lookup_result->second = lookup_result->second + 1;
+    }
+}
+
+std::unordered_map<utf8::utfchar32_t, unsigned int>::iterator context_occurrence::begin()
+{
+    return this->counts.begin();
+}
+
+std::unordered_map<utf8::utfchar32_t, unsigned int>::iterator context_occurrence::end()
+{
+    return this->counts.end();
+}
+
+void context_model::add(utf8::utfchar32_t character)
+{
+    if (this->current_context.size() >= 2)
+    {
+        std::string context_key;
+
+        for (const auto context_character: this->current_context)
+        {
+            utf8::append(context_character, context_key);
+        }
+        auto lookup_result = this->occurrences.find(context_key);
+
+        if (lookup_result == this->occurrences.end())
+        {
+            this->occurrences.insert({ context_key, context_occurrence(character) });
+        }
+        else
+        {
+            lookup_result->second.add(character);
+        }
+        this->current_context.pop_front();
+    }
+    this->current_context.push_back(character);
+}
+
+std::unordered_map<std::string, context_occurrence>::iterator context_model::begin()
+{
+    return this->occurrences.begin();
+}
+
+std::unordered_map<std::string, context_occurrence>::iterator context_model::end()
+{
+    return this->occurrences.end();
+}