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#include <stdio.h>

long long calc(long long k)
{
    long long ret = 0;
    while (k)
    {
        ret += (k % 10) * (k % 10);
        k /= 10;
    }
    return ret;
}

long long pp(long long a, long long b)
{
    long long ret = 1;
    while (b--)
        ret *= a;

    return ret;
}

int main()
{
    long long k, a, b;
    long long ans = 0;

    scanf("%lli %lli %lli", &k, &a, &b);

    //For i = 0 special case
    for (int i = 1; i < 10; ++i)
    {
        if (i >= a && i <= b && k * calc(i) == i)
            ++ans;
    }
   
    for (long long i = 1; i < 19; ++i)
    {
        long long start = pp (10, i);
        long long end = start * 10 - 1;

        if (start > b || end < a)
            continue;

        long long min_k = start / (i * 81);

        if (k < min_k)
            continue;

        long long val = start;

        if (start % k != 0)
            val = val - start % k + k;

        for (; val <= end; val += k)
        {
            if (val >= a && val <= b && k * calc(val) == val)
            {
                ++ans;
            }
        }
    }

    printf("%lli\n", ans);

    return 0;
}