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