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#include <iostream>

struct Result
{
    std::string value;
    int digits;
};

const long long PMIN = 1000000000ll;
const long long PMAX = 9999999999ll;

struct Num
{
    long long prefix;
    int mult;
    long long extra;

    // num = prefix * 10^mult + extra
    // extra < 10^mult
    // mult > 0 <=> 9999999999 > prefix > 1000000000
};

long long digits(long long n)
{
    if (n == 0) return 1;

    int d = 0;
    while (n > 0)
    {
        n /= 10;
        ++d;
    }
    return d;
}

long long digits(Num n)
{
    return digits(n.prefix) + n.mult;
}

long long pow10(int x)
{
    long long result = 1;
    for (int i=0;i<x;++i) result *= 10;
    return result;
}

long long nines(int n)
{
    if (n == 0) return 0;
    long long result = 9;
    if (n > 9) n = 9;
    for (int i=1;i<n;++i)
    {
        result *= 10;
        result += 9;
    }
    return result;
}

Num inc(Num x)
{
    if (x.mult == 0)
    {
        x.prefix++;
        if (x.prefix > PMAX)
        {
            x.mult = 1;
            x.extra = x.prefix % 10;
            x.prefix /= 10;
            return x;
        }
        return x;
    }
    x.extra++;
    if (digits(x.extra) > x.mult)
    {
        if (x.prefix+1 > PMAX)
        {
            x.prefix += 1;
            x.mult += 1;
            x.extra = x.prefix % 10;
            x.prefix /= 10;
            return x;
        }
        else
        {
            x.extra -= pow10(x.mult);
            x.prefix += 1;
            return x;
        }
    }
    return x;
}

Num roundUp(long long prefix, int d)
{
    long long pp = 1;
    while (pp <= prefix)
    {
        d--;
        pp*=10;
    }
    while (d > 0 && prefix < PMIN)
    {
        d--;
        prefix*=10;
    }
    return {prefix, d, 0};
}

Num roundUp2(long long prefix, int d)
{
    long long pp = 1;
    while (pp <= prefix)
    {
        d--;
        pp*=10;
    }
    while (d > 0 && prefix < PMIN)
    {
        d--;
        prefix*=10;
        prefix+=9;
    }
    return {prefix, d, nines(d)};
}

bool operator<(Num a, Num b)
{
    int da = digits(a);
    int db = digits(b);
    if (da != db) return da < db;
    if (a.prefix != b.prefix) return a.prefix < b.prefix;
    else return a.extra < b.extra;
}

Num solve(long long current, Num prev)
{
    long long dd = std::max(digits(prev), digits(current));
    Num new1 = roundUp(current, dd);
    //std::clog << " :: new1 = " << new1.prefix << " + 10^" << new1.mult << " + " << new1.extra << std::endl;
    if (prev < new1) return new1;

    Num new2 = roundUp2(current, dd);
    //std::clog << " :: new2 = " << new2.prefix << " + 10^" << new2.mult << " + " << new2.extra << std::endl;
    if (prev < new2) return inc(prev);

    else return roundUp(current, digits(prev)+1);
}

int main()
{
    int n;
    std::cin >> n;
    Num prev = {0,0,0};
    long long result = 0;
    for (int i=0;i<n;++i)
    {
        long long curr;
        std::cin >> curr;
        prev = solve(curr, prev);
        //std::clog << " :: " << prev.prefix << " + 10^" << prev.mult << " + " << prev.extra << std::endl;
        result += digits(prev) - digits(curr);
    }

    std::cout << result << std::endl;

    return 0;
}