#include <bits/stdc++.h>
int t, s, x;
int main() {
  scanf("%d%d%d", &t, &s, &x);
  if (x == t) {
    printf("YES\n");
    return 0;
  }
  for (int i = 1; i * s + t <= x; i++)
    if (i * s + t == x || i * s + t + 1 == x) {
      printf("YES\n");
      return 0;
    }
  printf("NO\n");
  return 0;
}
