#include<bits/stdc++.h>
using namespace std;
int n,s=0;
int f(int i){
	int r=0;
	if(i==1) r=n;
	else r=f(n-1)*10+n;
	return r;
}
int main(){
	cin>>n;
	for(int i=1;i<=n;i++){
		s=s+f(i);
	}
	cout<<s;
	return 0;
}
/**************************************************************
	Problem: 1245
	User: panyuchen
	Language: C++
	Result: Memory Limit Exceed
****************************************************************/