#include<bits/stdc++.h>
using namespace std;
int main(){
	int i,j=0,n,h=0,m=0;
	cin>>n;
	while(i<=n){
		while(j>0){
			h=h+j%10;
			j=j/10;
		}
		if(h==10){
		m=m+1;
		}
		i++;
    }
    cout<<m;
}
/**************************************************************
	Problem: 1985
	User: huanglingkai
	Language: C++
	Result: Wrong Answer
****************************************************************/