/in/foo.cc: In function 'int main()':
/in/foo.cc:8:15: error: lvalue required as left operand of assignment
   if(x*x*x*x= n)
               ^
/in/foo.cc:9:10: error: 'Yes' was not declared in this scope
    cout<<Yes;
          ^~~
/in/foo.cc:11:10: error: 'No' was not declared in this scope
    cout<<No;
          ^~