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#include <stdio.h>

long long sumOfSquares(long long number) {
    long long result = 0;
    while(number > 0) {
        result += (number % 10) * (number % 10);
        number /= 10;
    }
    return result;
}

int main() {
    long long k, a, b;
    scanf("%lld %lld %lld", &k, &a, &b);

    long long result = 0;
    for(long long i = a + (a % k == 0? 0 : (k - a % k)); i <= b && i / 18 / 9 / 9 <= k; i += k) {
        if(i / k == sumOfSquares(i)) {
            ++result;
        }
    }

    printf("%lld\n", result);
    return 0;
}