Compilare: user.cpp: In function ‘int main()’: user.cpp:39:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<g[x].size();i++) ^ user.cpp:26:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sate.in","r",stdin); ^ user.cpp:27:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("sate.out","w",stdout); ^ user.cpp:28:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&x,&y); ^ user.cpp:31:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&xx,&yy,&z); ^