Compilare: user.cpp: In function ‘void dfs(long int)’: user.cpp:26:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<M[nod].size();i++) ^ user.cpp: In function ‘void dfs2()’: user.cpp:49:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0;i<M[sav.nod].size();i++) ^ user.cpp: In function ‘int main()’: 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("dragoni.in","r",stdin); ^ user.cpp:68:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld",&t); ^ user.cpp:69:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld",&n,&m); ^ user.cpp:72:27: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld",&v[i]); ^ user.cpp:76:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%ld%ld%ld",&a,&b,&d); ^