Compilare: user.cpp: In function ‘int main()’: user.cpp:19:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(co=0;co<v[y].size();co++) ^ user.cpp:33:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(co=0;co<v[y].size();co++) ^ user.cpp:32:16: warning: unused variable ‘pp’ [-Wunused-variable] int co,pp=0; ^ user.cpp:43:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(co=0;co<v[y].size();co++) ^ user.cpp:9:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hashuri.in","r",stdin); ^ user.cpp:10:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hashuri.out","w",stdout); ^ user.cpp:11:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:14:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&j,&x); ^