#include<bits/stdc++.h>
using namespace std;
int a(int n){
  int s=0;
  while(n){
  s=s+n%10;
  n=n/10;
  }
return s;
} 
int main(){
  int i,x=0,n;
  cin>>n;
  for(i=1;i<=n;i++)
  	if(a(i)==13) x++;
  	cout<<x;
return 0;
}
/**************************************************************
	Problem: 1511
	User: wtq001
	Language: C++
	Result: Accepted
	Time:101 ms
	Memory:2072 kb
****************************************************************/