Compilare: main.cpp: In function 'int main()': main.cpp:54:15: warning: suggest explicit braces to avoid ambiguous 'else' [-Wparentheses] if(_M[i]) ^ main.cpp:32:38: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("marceland.in","r",stdin); ^ main.cpp:33:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("marceland.out","w",stdout); ^ main.cpp:34:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ main.cpp:37:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d\n",&n,&m); ^