#include<iostream>
#include<cstdio>
#include<vector>
#include<cmath>
#include<climits>
using namespace std;

int pow(int a, int b){
    int ret=1;
    for (int i=0;i<b;i++)
    ret*=a;
   return ret;   
}

int main(){
 
	long long n;
	cin>>n;
	long long x=n;
	long long count=0;
	while(x>0){
 
		count++;
		x/=10;
	}
	long long ans=0;
	ans=(n-pow(10,count-1)+1)*count;
	for(long long i=count-2;i>=0;i--){
 
		ans+=9*pow(10,i)*(i+1);
	}
	cout<<ans<<endl;
	cin.get();
	cin.get();
	return 0;
}