#include <bits/stdc++.h>
typedef long long ll;
const int INF = 1e9;
const ll LINF = 1e18;
const int MOD = 1e9+7;
using namespace std;

int main() {
  int a, b;
  if (a - 1 == b) {
    cout << "YES" << endl;
  } else {
    cout << "NO" << endl;
    cout << abs(a + 1 - b) << endl;
  }
}