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#include <cstdio>
#include <cstring>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <iterator>
#include <string>
#include <vector>
#include <queue>
#include <bitset>
#include <utility>
#include <stack>
#include <string>

using namespace std;
typedef long long LL;
typedef pair<int,int> PII;
typedef vector<int> VI;
#define MP make_pair
#define FOR(v,p,k) for(int v=(p);v<=(k);++v)
#define FORD(v,p,k) for(int v=(p);v>=(k);--v)
#define REP(i,n) for(int i=0;i<(n);++i)
#define VAR(v,i) __typeof(i) v=(i)
#define FOREACH(i,c) for(VAR(i,(c).begin());i!=(c).end();++i)
#define PB push_back
#define ST first
#define ND second
#define SIZE(x) (int)x.size()
#define ALL(c) c.begin(),c.end()

#define ODD(x) ((x)%2)
#define EVEN(x) (!(ODD(x)))

const LL MAX_PREF = 1e16;
// very risky to use for other tasks!!!
struct BigNumApprox {
    LL pref;
    int extra_len;

    BigNumApprox(int x) : pref(x), extra_len(0) {}

    bool lt(BigNumApprox &b) {
        //assert(b.extra_len == 0);
        return (extra_len == 0) && (pref < b.pref);
    }

    bool eq(BigNumApprox &b) {
        //assert(b.extra_len == 0);
        return (extra_len == 0) && (pref == b.pref);
    }

    void mul10(int k) {
        //assert(k>=0);
        if (k == 0) {
            return;
        }
        if (extra_len > 0) {
            extra_len += k;
            return;
        }

        while(true) {
            pref *= 10;
            --k;
            if (pref >= MAX_PREF) {
                pref /= 10;
                extra_len += k+1;
                return;
            }
            if (k==0) {
                return;
            }
        }
    }

    int lex_cmp(BigNumApprox &b) {
        //assert(b.extra_len == 0);
        auto a_str = to_string(pref);
        auto b_str = to_string(b.pref);
        return a_str.compare(b_str);
    }

    bool lex_lt(BigNumApprox &b) {
        //assert(b.extra_len == 0);
        return lex_cmp(b) < 0;
    }

    int lex_len() {
        return extra_len + to_string(pref).length();
    }

    bool starts_with(BigNumApprox &b) {
        //assert(b.extra_len == 0);
        auto a_str = to_string(pref);
        auto b_str = to_string(b.pref);

        if (b_str.length() > a_str.length()) {
            return false;
        }
        //https://stackoverflow.com/questions/7913835/check-if-one-string-is-a-prefix-of-another
        auto res = std::mismatch(b_str.begin(), b_str.end(), a_str.begin());

        return (res.first == b_str.end());
    }

    void inc() {
        ++pref;
        if (pref == MAX_PREF) {
            pref /= 10;
            ++extra_len;
        }
    }


};



int main() {
    LL ret=0;
    int n, aa;
    scanf("%d\n%d", &n, &aa);
    BigNumApprox a = BigNumApprox(aa);
    BigNumApprox b = a;

    FOR(i,1,n-1) {
        a = b;
        int bb;
        scanf("%d", &bb);
        b = BigNumApprox(bb);

        if (a.lt(b)) {
            continue;
        }
        if (a.eq(b)) {
            b.mul10(1);
            ret += 1;
            continue;
        }
        //assert(a.gt(b));
        int k = a.lex_len() - b.lex_len();
        //assert(k>=0);
        if (a.lex_lt(b)) {
            b.mul10(k);
            ret += k;
            continue;
        }
        if (!a.starts_with(b)) {
            b.mul10(k+1);
            ret += k+1;
            continue;
        }
        //assert(a.starts_with(b));
        a.inc();
        if (a.starts_with(b)) {
            b=a;
            ret += k;
            continue;
        }
        //a-1 == b99999999
        b.mul10(k+1);
        ret += k+1;
        continue;
    }
    printf("%lld\n", ret);
    return 0;
}