#include <iostream>
using namespace std;
 
int main(){ 
    int n,i,j,s=0,c=0;
    cin>>n;
    for(i=1;i<=n;i++){
    	for(j=1;j<=i;j++){
    		c=c*10+n;
		}
		s+=c;
		c=0;
	}
	cout<<s<<endl;
}
/**************************************************************
	Problem: 1245
	User: admin
	Language: C++
	Result: Accepted
	Time:9 ms
	Memory:2072 kb
****************************************************************/