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#include <cassert>
#include <cstring>
#include <iostream>
#include <string>

#define TS_DEBUG 0

#if !TS_DEBUG
#define NDEBUG
#endif

const int MAX_DIGITS = 256*1024;

class Huge
{
private:
    int n;
    char digits[MAX_DIGITS];

public:
    Huge() : n(1) { digits[0] = 0; }
    Huge & operator=(const Huge& src);

    int length() { return n; }
    int CompareTo(const Huge& other);
    int CompareToPrefixOf(const Huge& other);
    int IsPrefixOf(const Huge& other);

    void AppendZeros(int zeroCount);
    void SetToZeroExtended(const Huge& src, int zeroCount);
    void SetToIncremented(const Huge& src);

    friend std::istream& operator>>(std::istream& is, Huge& value);
    friend std::ostream& operator<<(std::ostream& os, const Huge& value);
};

Huge & Huge::operator=(const Huge& src)
{
    if (this != &src) {
        n = src.n;
        memcpy(digits, src.digits, src.n);
    }
    return *this;
}

int Huge::CompareTo(const Huge& other)
{
    if (n < other.n) {
        return -1;
    } else if (n == other.n) {
        return memcmp(digits, other.digits, n);
    } else {
        return 1;
    }
}

int Huge::CompareToPrefixOf(const Huge& other)
{
    assert(n <= other.n);
    return memcmp(digits, other.digits, n);
}

int Huge::IsPrefixOf(const Huge& other)
{
    return n <= other.n && CompareToPrefixOf(other) == 0;
}

void Huge::AppendZeros(int zeroCount)
{
    assert(0 <= zeroCount);
    for (int i = 0; i < zeroCount; i++) {
        digits[n++] = 0;
    }
}

void Huge::SetToZeroExtended(const Huge& src, int zeroCount)
{
    n = src.n + zeroCount;
    memcpy(digits, src.digits, src.n);
    memset(&digits[src.n], 0, zeroCount);
}

void Huge::SetToIncremented(const Huge& src)
{
    n = src.n;
    int c = 1;
    for (int i = src.n - 1; i >= 0; i--) {
        int s = src.digits[i] + c;
        int d = s < 10 ? s : s - 10;
        c = s < 10 ? 0 : 1;
        digits[i] = d;
    }
    if (c > 0) {
        memmove(&digits[1], &digits[0], n);
        digits[0] = 1;
        n++;
    }
}

std::istream& operator>>(std::istream& is, Huge& value)
{
    std::string input;
    is >> input;
    int m = input.length();
    int i = 0;
    while (i < m && (isspace(input[i]) || input[i] == '0')) {
        i++;
    }
    int n = 0;
    while (i < m && isdigit(input[i])) {
        value.digits[n] = input[i] - '0';
        n++;
        i++;
    }
    value.n = n;
    return is;
}

std::ostream& operator<<(std::ostream& os, const Huge& value)
{
    for (int i = 0; i < value.n; i++) {
        char c = '0' + value.digits[i];
        os << c;
    }
    return os;
}


void debug1(const Huge& x, const Huge& x1)
{
#if TS_DEBUG
    std::cerr << "[" << x << "] -> [" << x1 << "]\n";
#endif
}


void debug2(const char* name, const Huge& x)
{
#if TS_DEBUG
    std::cerr << name << " = [" << x << "]\n";
#endif
}


int main()
{
    long long result = 0;

    int n;
    std::cin >> n;
    Huge a;
    Huge b;
    Huge b1;
    Huge d;
    std::cin >> a;
    debug1(a, a);
    for (int i = 1; i < n; i++) {
        std::cin >> b;
        int cmp = b.CompareTo(a);
        if (cmp > 0) {
            b1 = b;
        } else if (cmp == 0) {
            b1.SetToZeroExtended(b, 1);
        } else {
            assert(cmp < 0);
            int lenDiff = a.length() - b.length();
            if (lenDiff == 0) {
                b1.SetToZeroExtended(b, 1);
            } else {
                int cmpPre = b.CompareToPrefixOf(a);
                if (cmpPre > 0) {
                    b1.SetToZeroExtended(b, lenDiff);
                } else if (cmpPre == 0) {
                    d.SetToIncremented(a);
                    debug2("d", d);
                    if (b.IsPrefixOf(d)) {
                        b1 = d;
                    } else {
                        b1.SetToZeroExtended(b, lenDiff + 1);
                    }
                } else {
                    b1.SetToZeroExtended(b, lenDiff + 1);
                }
            }
        }
        debug1(b, b1);
        assert(b1.CompareTo(a) > 0);
        assert(b.IsPrefixOf(b1));
        result += b1.length() - b.length();
        a = b1;
    }

    std::cout << result << '\n';

    return 0;
}