/in/foo.cc: In function 'int com()':
/in/foo.cc:39:1: warning: no return statement in function returning non-void [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:60:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for(int i=1;i<=n;i++) cout<<ans[i]<<" "; cout<<endl;
  ^~~
/in/foo.cc:60:43: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
  for(int i=1;i<=n;i++) cout<<ans[i]<<" "; cout<<endl;
                                           ^~~~
/in/foo.cc: In function 'int dfs2(int, int)':
/in/foo.cc:20:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^
/in/foo.cc: In function 'int dfs(int, int)':
/in/foo.cc:53:1: warning: control reaches end of non-void function [-Wreturn-type]
 }
 ^