Compilare: user.cpp: In function ‘int main()’: user.cpp:82:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0,printf("%d\n",leader.size());i<leader.size();++i) ^ user.cpp:51:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pamant.in","r",stdin); ^ user.cpp:52:33: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("pamant.out","w",stdout); ^ user.cpp:54:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&N,&M); ^ user.cpp:58:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&X,&Y); ^