Compilare: main.cpp: In function 'int main()': main.cpp:141:43: 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:142:45: 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:145:35: 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:151:41: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%d", &value); ^ main.cpp:159:50: 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:167:45: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] std::scanf("%d", &x); ^