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