Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:26:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<vecin[nod].size();i++){ ^ user.cpp: In function ‘int main()’: user.cpp:72:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<comp[i].size();j++) ^ user.cpp:76:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<ans[i].size();j++) ^ user.cpp:54:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("biconex.in","r",stdin); ^ user.cpp:55:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("biconex.out","w",stdout); ^ user.cpp:58:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&n,&m); ^ user.cpp:62:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&x,&y); ^