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#include <cstdio>
using namespace std;

unsigned long long int k, a, b, n, N;
int main()
{
    scanf("%llu %llu %llu", &k, &a, &b);
    int result = 0;
    for(int fn = 0; fn <= 18 * 81; ++fn)
    {
        int fn_prop = 0;
        N = n = k * fn;
        for(int i=0; i<=18; ++i){ fn_prop += (n%10)*(n%10); n = n / 10; }
        if ((fn == fn_prop) && (N>=a) && (N<=b)) ++result;
    }

    printf("%d\n", result);
}