#include <iostream>
#include <string>

using namespace std;

int d(long long n) {
    return to_string(n).length();   
}

long long pow1(long long n){
    if (n == 0){
        return 1;
    }
    long long result = 1;
    for(int i = 0; i < n; i++) {
        result *= 10;
    }
    return result;
}

int main() {
    long long size;
    long long res = 0;
    cin >> size;
    long long prev = 0;
    long long curr;
    long long a, b, df, x;
    for(long long i = 0; i < size; i++){
        // cout << prev << endl;
        cin >> curr;
        if (curr > prev) {
            prev = curr;
            continue;   
        }
        a = d(curr);
        b = d(prev);
        if (a == b) {
            res += 1;
            curr *= 10;
            prev = curr;
            continue;
        }
        df = b - a;
        curr *= pow1(df);
        if (curr > prev) {
            res += df;
            prev = curr;
            continue;
        } else {
            if (pow1(df) - 1 > prev - curr) {
                curr = prev + 1;
                prev = curr;
                res += df;
                continue;
            } else {
                res += df + 1;
                curr *= 10;
                prev = curr;
            }
        }
    }
    cout << res;
    return 0;
}