Compilare: user.cpp: In function ‘void bfs(int)’: user.cpp:35:39: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<M[nod].size();i++) ^ user.cpp: In function ‘void dfs(int, int, long long int)’: user.cpp:50:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<M[nod].size();i++) ^ user.cpp: In function ‘int main()’: user.cpp:86:45: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("symmetricgraph2.in","r",stdin); ^ user.cpp:87:47: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("symmetricgraph2.out","w",stdout); ^ user.cpp:91:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d",&n,&m); ^ user.cpp:93:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d%d%d",&x,&y,&z); ^