Compilare: main.cpp: In function 'void solve(int, int, std::vector<std::pair<int, int> >&)': main.cpp:95:17: warning: unused variable 'sum' [-Wunused-variable] int sum = t; ^~~ main.cpp: At global scope: main.cpp:148:28: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type] main(int argc, char *argv[]) ^ main.cpp: In member function 'char InParser::read_ch()': main.cpp:19:29: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^