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