Compilare: main.cpp: In function 'int main()': main.cpp:146:43: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] std::freopen("mit.in", "r", stdin); ^ main.cpp:147:45: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] std::freopen("mit.out", "w", stdout); ^ main.cpp:150:35: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%u%u", &N, &M); ^ main.cpp:156:41: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%d", &value); ^ main.cpp:164:50: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%d%d%d", &op, &a, &b); ^ main.cpp:172:45: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%d", &x); ^