/in/foo.cc: In function 'void fohuj()':
/in/foo.cc:19:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<b[x].size();i++)qa[b[x][i]]--;
               ~^~~~~~~~~~~~
/in/foo.cc:21:58: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=1;i<=n;i++){if(qa[i]==1){flag=1;for(int j=0;j<a[i].size();j++)if(!vis[a[i][j]]){p.push(a[i][j]);ans[i]=a[i][j];vis2[i]=1;qj++;break;}break;}}
                                                         ~^~~~~~~~~~~~