Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:12:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G[nod].size(); i++) ^ user.cpp: In function ‘void DFS1(int)’: user.cpp:19:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<G1[nod].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:49:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<st1.size(); i++) ^ user.cpp:25:32: 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:26:34: 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:27:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:30:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^