Compilare: main.cpp: In function 'int main()': main.cpp:108:26: warning: ISO C++ forbids converting a string constant to 'char*' [-Wwrite-strings] InParser in("tango2.in"); ^ main.cpp:109:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("tango2.out", "w", stdout); ^ main.cpp: In member function 'char InParser::read_ch()': main.cpp:30:55: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buffer, sizeof(buffer[0]), BUFF_SIZE, fin); ^