Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:18:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i< g[nod].size() ; i++) ^ user.cpp: In function ‘void dfst(int)’: user.cpp:30:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i<gt[nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:65:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (j=0;j<ctc[i].size();j++) ^ user.cpp:40:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.in","r",stdin); ^ user.cpp:41:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out","w",stdout); ^ user.cpp:43:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:46:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^