#include <bits/stdc++.h>
using namespace std;
int main() {
  int x, t, s;
  cin >> t >> s >> x;
  if ((((x - t) % s == 0) ||
       (((x - t - 1) % s == 0) && ((x - t - 1) / s != 0))) &&
      (x >= t))
    cout << "YES";
  else
    cout << "NO";
}
