Compilare: main.cpp: In function 'int main()': main.cpp:79:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j = 0 ; j < Q[i].size() ; j ++) ~~^~~~~~~~~~~~~ main.cpp:59:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("calafat.in" , "r" , stdin); ^ main.cpp:60:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("calafat.out" , "w" , stdout); ^ main.cpp:62:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &n , &m); ^ main.cpp:65:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d" , &v[i]); ^ main.cpp:74:32: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d" , &x , &y); ^