int main() {
 unsigned int square_of_sum = 0;
 unsigned int sum_of_square = 0;
 unsigned int n = 1;
 while(n <= 100) {
  square_of_sum += n;
  ++n;
 }
 square_of_sum *= square_of_sum;
 
 n = 1;
 while(n <= 100) {
  sum_of_square += n*n;
  ++n;
 }

 std::cout << square_of_sum - sum_of_square << std::endl;
}

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