#include <bits/stdc++.h>
#define ll long long
#define int long long
#define mod 1000000007
using namespace std;

ll fastpow(ll n, ll x) {

	if (x == 0) {
		return 1;
	}
	else {
		ll ret = fastpow(n, x / 2);
		ret = ((ret) * (ret));
		if (x % 2 == 0) {
			return ret;
		}
		else {
			return ((ret) * (n));
		}
	}
}
bool check(ll n){
    ll first = n %10;
    while( n> 0 ){
        if(n%10 != first){
            return false;
        }
        n/=10;
    }
    return true;
}
int Log10n(int n){
    int c = -1;
    while(n > 0){
        c++;
        n/=10;
    }
    return c;
}
ll sosanh[11];
void solve(){
   ll n;
   cin >> n;
   int mu  = fastpow(10, Log10n(n));
   int chuso = Log10n(n);
   ll first = n / mu;
   if(n < 10){
    cout << n + 1;
   }
   else{
    ll ans = chuso;
    for(int i = 1; i < first; i++){
        ans += chuso + 1;
    }
    if(n >= sosanh[chuso + 1]*first){
        ans += chuso + 1;
    }
    else{
        ans += chuso;
    }
    for(int i = first + 1; i < 10; i++){
        ans += chuso;
    }
    cout<< ans;
   }
}

signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cout.tie(NULL);
    sosanh[1] = 1;
    for(int i = 1; i <= 10; i++){
        sosanh[i] = sosanh[i-1]*10 + 1;
    }
    
    solve();
}