1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 | #include <cstdio>
long long f(long long n) {
long long ret = 0;
while (n != 0) {
long long v = n % 10;
ret += v * v;
n /= 10;
}
return ret;
}
int main() {
long long k, a, b;
scanf("%lld%lld%lld", &k, &a, &b);
long long result = 0;
for (long long i = a + k - a % k; i <= b; i += k) {
if (i / k == f(i))
result++;
}
printf("%lld\n", result);
return 0;
}
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