/in/foo.cc: In function 'int add(int, int)':
/in/foo.cc:11:69: warning: no return statement in function returning non-void [-Wreturn-type]
 inline int add(int x,int y){son[++tot]=y;nxt[tot]=lnk[x];lnk[x]=tot;}
                                                                     ^
/in/foo.cc: In function 'int main()':
/in/foo.cc:19:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  if (!D[i]) q.push(i);tmp=n;
  ^~
/in/foo.cc:19:23: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'if'
  if (!D[i]) q.push(i);tmp=n;
                       ^~~
/in/foo.cc:18:2: warning: this 'for' clause does not guard... [-Wmisleading-indentation]
  for (int i=1;i<=n;i++)
  ^~~
/in/foo.cc:19:23: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'for'
  if (!D[i]) q.push(i);tmp=n;
                       ^~~