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#include <stdio.h>

unsigned int square_digits(unsigned long number) {
    unsigned int acc = 0;
    unsigned int last;
    do {
        last = number % 10;
        acc += last * last;
        number /= 10;
    } while (number > 0);
    return acc;
}

int main() {
    unsigned long k, a, b;

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

    int result = 0;
    unsigned long i;
    for(i = a; i < b+1; i++) {
        if (k * square_digits(i) == i) {
            result++;
        }
    }
    printf("%d\n", result);
    return 0;
}