foo.cc: In function 'int main()':
foo.cc:9:13: warning: right operand of comma operator has no effect [-Wunused-value]
    9 |     cin>>m,n;
      |             ^
foo.cc:7:11: warning: 'n' may be used uninitialized in this function [-Wmaybe-uninitialized]
    7 |     int m,n;
      |           ^
foo.cc:36:11: warning: 'cnt' may be used uninitialized in this function [-Wmaybe-uninitialized]
   36 |     cout<<cnt<<endl;
      |           ^~~

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