function to check if there exist two numbers sum of whose squares is n .
bool sumSquare ( int n ) { for ( long i = 1 ; i * i <= n ; i ++ ) for ( long j = 1 ; j * j <= n ; j ++ ) if ( i * i + j * j == n ) { cout << i << " ^ 2 ▁ + ▁ " << j << " ^ 2" << endl ; return true ; } return false ; }