#include <bits/stdc++.h>
using namespace std;
int main() {
  int a, b, c, res = 2;
  cin >> a >> b >> c;
  if (c == a) res = 0;
  if (c - a > 1 && (c - a) % b == 0) res = 0;
  if (c - a > 1 && (c - a) % b == 1) res = 0;
  if (res == 0)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
