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#include <cstdio>

bool check(long long num, int sum) {
  while (num) {
    int d = num%10;
    sum -= d*d;
    num /= 10;
  }
  return sum == 0;
}

int main() {
  long long k, a, b;
  scanf("%lld%lld%lld", &k, &a, &b);
  long long i = (a+k-1)/k;
  int c = 0;
  for (long long num = i*k; num < b && i < 2000; ++i, num += k) {
    if (check(num, i)) {
      ++c;
    }
  }
  printf("%d\n", c);
}