Help me in solving USR2V2 problem

My issue

code of this question

My code

#include <iostream>
using namespace std;

int main() {

  int a, b;
  int sum;
  int diff;
  cin >> a;
  cin >> b;
  cout<<"Sum is:"<< sum<<endl;
  cout<<"Difference is:"<< diff;

  return 0;

Learning course: Learn C++
Problem Link: CodeChef: Practical coding for everyone

U have to leave space after is: