Compilare: user.cpp: In function ‘void solve()’: user.cpp:97:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < t.size();) ^ user.cpp:102:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < t.size() && t[i] == p) ^ user.cpp:115:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (i < t.size() && t[i] == p) ^ user.cpp: In constructor ‘InputReader::InputReader(const char*)’: user.cpp:30:43: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In member function ‘void InputReader::advance()’: user.cpp:57:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buffer, SIZE, 1, input_file); ^ user.cpp: In function ‘void write()’: user.cpp:130:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("praslea.out", "w", stdout); ^