Добавлена третья задача пятой главы

Занимательное программирование/5/3_context/context.hpp

@@ -0,0 +1,27 @@
+#include <list>
+#include "utf8.h"
+#include <unordered_map>
+
+struct context_occurrence
+{
+    unsigned int count{ 1 };
+    std::unordered_map<utf8::utfchar32_t, unsigned int> counts;
+
+    explicit context_occurrence(utf8::utfchar32_t character);
+    void add(utf8::utfchar32_t character);
+
+    std::unordered_map<utf8::utfchar32_t, unsigned int>::iterator begin();
+    std::unordered_map<utf8::utfchar32_t, unsigned int>::iterator end();
+};
+
+struct context_model
+{
+    void add(utf8::utfchar32_t character);
+
+    std::unordered_map<std::string, context_occurrence>::iterator begin();
+    std::unordered_map<std::string, context_occurrence>::iterator end();
+
+private:
+    std::list<utf8::utfchar32_t> current_context;
+    std::unordered_map<std::string, context_occurrence> occurrences;
+};