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
26
27
28
#include <stdio.h>

long long sum2(long long n){
  int s = 0;
  while(n){
    int r = n%10;
    n/=10;
    s+=r*r;
  }
  return s;
}

long long k,a,b,A,B;
long long M = 1458;
int len = 0;

int main()
{
  scanf("%lld%lld%lld",&k,&a,&b);
  A = (a+k-1)/k;
  B = b/k;
  if (B>M) B = M;
  for(long long m = A;m<=B;++m)
    if(m == sum2(m*k)) len++;
  printf("%d\n",len);

  return 0;
}