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#include <bits/stdc++.h>

using namespace std;
using LL = long long;

void initialize()
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
}

int digit_count(LL x)
{
    int count = 0;
    while (x > 0)
    {
        count++;
        x /= 10;
    }
    return count;
}

LL fast_pow(LL x, int y)
{
    if (y == 0)
        return 1;
    if (y == 1)
        return x;
    LL temp = fast_pow(x, y >> 1);
    if (y & 1)
        return temp * temp * x;
    return temp * temp;
}

int main()
{
    initialize();

    int n;
    cin >> n;

    LL answer = 0;
    LL prev = 0, zeroes = 0, add = 0;
    for (auto i = 0; i < n; i++)
    {
        LL a;
        cin >> a;

        LL a_digits = digit_count(a), prev_digits = digit_count(prev);
        LL digits_diff = a_digits - prev_digits;

        if (a_digits > prev_digits + zeroes)
        {
            prev = a, zeroes = 0, add = 0;
            continue;
        }

        auto base_a = [&] { return a / fast_pow(10, max(LL(0), digits_diff)); };
        auto base_prev = [&] { return prev / fast_pow(10, max(LL(0), -digits_diff)); };

        if (base_a() > base_prev())
        {
            prev = a, zeroes -= digits_diff, add = 0;
            answer += zeroes;
            continue;
        }

        if (base_a() < base_prev())
        {
            prev = a, zeroes -= digits_diff - 1, add = 0;
            answer += zeroes;
            continue;
        }

        if (a_digits < prev_digits)
        {
            add++;
            if (zeroes < 10 and add == fast_pow(10, zeroes))
            {
                prev++;
                if (base_a() != base_prev())
                {
                    prev = a, zeroes -= digits_diff - 1, add = 0;
                    answer += zeroes;
                }
                else
                {
                    add = 0;
                    answer += zeroes;
                }
            }
            else
            {
                answer += zeroes;
            }
        }

        if (a_digits >= prev_digits)
        {
            if (zeroes < 10)
            {
                LL temp_a = a % fast_pow(10, digits_diff), temp_b = add / fast_pow(10, zeroes - digits_diff);
                if (temp_a < temp_b)
                {
                    prev = a, zeroes -= digits_diff - 1, add = 0;
                    answer += zeroes;
                }
                if (temp_a > temp_b)
                {
                    prev = a, zeroes -= digits_diff, add = 0;
                    answer += zeroes;
                }
                if (temp_a == temp_b)
                {
                    add++;
                    if (add >= fast_pow(10, zeroes - digits_diff))
                    {
                        prev = a, zeroes -= digits_diff - 1, add = 0;
                        answer += zeroes;
                    }
                    else
                    {
                        prev = a, zeroes -= digits_diff;
                        answer += zeroes;
                    }
                }
            }
            else
            {
                prev = a, zeroes -= digits_diff, add = 0;
                answer += zeroes;
            }
        }
    }

    cout << answer << '\n';

    return 0;
}