#include<bits/stdc++.h>

using namespace std;

typedef long long ll;

ll n,  k = 1;

ll pow1(int l) {
	ll k1 = 1;
	for (int i = 1; i <= l; ++i) {
		k1 = k1 * 10;
	}
	return k1;
}

int main() {
	cin >> n;
	ll j;
	for (ll i = 1; pow1(i) <= n; i++) {
		k = k + (n % pow1(i + 1) / pow1(i)) * pow1(i - 1) * (i + 1);
		j = i;
	}
	if (n % 10 != 0) {
		k = k + j + 1;
	}
	cout << k;

	return 0;
}