foo.cc: In function 'int main()':
foo.cc:21:20: error: 'i' was not declared in this scope
   21 |                 if(i==j) cout<<"NO"<<endl;
      |                    ^
foo.cc:21:23: error: 'j' was not declared in this scope
   21 |                 if(i==j) cout<<"NO"<<endl;
      |                       ^

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