foo.cc: In function 'int main()':
foo.cc:27:14: warning: 'ey' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |   if(hd.x==ex&&hd.y==ey){cout<<hd.second<<endl;return 0;}
      |      ~~~~~~~~^~~~~~~~~~
foo.cc:27:3: warning: 'ex' may be used uninitialized in this function [-Wmaybe-uninitialized]
   27 |   if(hd.x==ex&&hd.y==ey){cout<<hd.second<<endl;return 0;}
      |   ^~

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