Compilare: main.cpp:5:0: warning: ignoring #pragma GCC optimization [-Wunknown-pragmas] #pragma GCC optimization ("unroll-loops") main.cpp: In function 'void IOfile()': main.cpp:47:32: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("custi.in", "r", stdin); ^ main.cpp:48:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("custi.out", "w", stdout); ^