Compilare: user.cpp: In function ‘int main()’: user.cpp:50:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int l=0;l<poz[j].size();l++){ ^ user.cpp:63:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int l=0;l<poz[i].size();l++){ ^ user.cpp:71:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int l=0;l<poz[i].size();l++){ ^ user.cpp:35:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mexc.in","r",stdin); ^ user.cpp:36:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("mexc.out","w",stdout); ^ user.cpp:39:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d",&n,&m,&d); ^ user.cpp:43:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d",&a[i][j].first); ^