foo.cc: In function 'int main()':
foo.cc:41:49: warning: unused variable 'w' [-Wunused-variable]
   41 |                         int u = Q.top().second, w = Q.top().first; Q.pop();
      |                                                 ^
foo.cc:36:21: warning: unused variable 'ans2' [-Wunused-variable]
   36 |                 int ans2 = 0, cnt2 = 0;
      |                     ^~~~
foo.cc:50:23: warning: 'pos' may be used uninitialized in this function [-Wmaybe-uninitialized]
   50 |                 printf( "%d ", n - pos );
      |                 ~~~~~~^~~~~~~~~~~~~~~~~~

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