Compilare: user.cpp: In function ‘void DFS(int)’: user.cpp:18:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ^ user.cpp:24:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ^ user.cpp:31:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < v[nod].size(); ++i) ^ user.cpp:55:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i <= v[nod].size(); ++i) ^ user.cpp: In function ‘int main()’: user.cpp:66:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("karb2.in","r",stdin); ^ user.cpp:67:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("karb2.out","w",stdout); ^ user.cpp:69:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&k); ^ user.cpp:73:23: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&x); ^ user.cpp:79:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^