foo.cc: In function 'int main()':
foo.cc:17:21: warning: unused variable 'ans' [-Wunused-variable]
   17 |     int n,i,l,r,mid,ans,z,y;
      |                     ^~~
foo.cc:45:21: warning: 'y' may be used uninitialized in this function [-Wmaybe-uninitialized]
   45 |      cout<<z<<endl<<y;
      |                     ^
foo.cc:45:12: warning: 'z' may be used uninitialized in this function [-Wmaybe-uninitialized]
   45 |      cout<<z<<endl<<y;
      |            ^

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