foo.cc: In function 'int main()':
foo.cc:4:2: error: 'cin' was not declared in this scope
    4 |  cin>>a>>b;
      |  ^~~
foo.cc:8:3: error: 'cout' was not declared in this scope
    8 |   cout<<"Yes"<<endl;
      |   ^~~~
foo.cc:8:16: error: 'endl' was not declared in this scope
    8 |   cout<<"Yes"<<endl;
      |                ^~~~
foo.cc:10:3: error: 'cout' was not declared in this scope
   10 |   cout<<"No"<<endl;
      |   ^~~~
foo.cc:10:15: error: 'endl' was not declared in this scope
   10 |   cout<<"No"<<endl;
      |               ^~~~

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