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#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>

using namespace std;
#define PB push_back
#define MP make_pair
#define LL long long
#define int LL
#define FOR(i,a,b) for(int i = (a); i <= (b); i++)
#define RE(i,n) FOR(i,1,n)
#define REP(i,n) FOR(i,0,(int)(n)-1)
#define R(i,n) REP(i,n)
#define VI vector<int>
#define PII pair<int,int>
#define LD long double
#define FI first
#define SE second
#define st FI
#define nd SE
#define ALL(x) (x).begin(), (x).end()
#define SZ(x) ((int)(x).size())

#define unordered_map __fast_unordered_map
template<class Key, class Value, class Hash = std::hash<Key>>
using unordered_map = __gnu_pbds::gp_hash_table<Key, Value, Hash>;

template<class C> void mini(C &a4, C b4) { a4 = min(a4, b4); }
template<class C> void maxi(C &a4, C b4) { a4 = max(a4, b4); }

template<class TH> void _dbg(const char *sdbg, TH h){ cerr<<sdbg<<'='<<h<<endl; }
template<class TH, class... TA> void _dbg(const char *sdbg, TH h, TA... a) {
  while(*sdbg!=',')cerr<<*sdbg++;
  cerr<<'='<<h<<','; _dbg(sdbg+1, a...);
}

template<class T> ostream &operator<<(ostream& os, vector<T> V) {
  os << "["; for (auto vv : V) os << vv << ","; return os << "]";
}
template<class L, class R> ostream &operator<<(ostream &os, pair<L,R> P) {
  return os << "(" << P.st << "," << P.nd << ")";
}

#ifdef LOCAL
#define debug(...) _dbg(#__VA_ARGS__, __VA_ARGS__)
#else
#define debug(...) (__VA_ARGS__)
#define cerr if(0)cout
#endif

#ifdef LARGE_BOUND
const int kLargeNumBound = LARGE_BOUND;
const int kLargeNumPrefix = LARGE_PREFIX;
#else
const int kLargeNumBound = 17;
const int kLargeNumPrefix = 10;
#endif

bool IsPrefix(const string &pref, const string &num) {
  return SZ(pref) <= SZ(num) && equal(ALL(pref), num.begin());
}

int32_t main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout << fixed << setprecision(11);
  cerr << fixed << setprecision(6);

  int N;
  cin >> N;

  LL answer = 0;

  bool is_large_num = false;
  string cur_small_number = "";
  string large_num_prefix;
  int num_len;

  for (int i = 0; i < N; ++i) {
    string v;
    cin >> v;
  
    if (!is_large_num) {
      if (SZ(cur_small_number) < SZ(v)) {
        cur_small_number = v;
        continue;
      }

      cur_small_number = to_string(stoll(cur_small_number) + 1);
      if (IsPrefix(v, cur_small_number)) {
        answer += SZ(cur_small_number) - SZ(v);
        continue;
      }

      const int cur_len = SZ(cur_small_number);
      const int new_len = cur_len + (v < cur_small_number);

      cur_small_number = v + string(new_len - SZ(v), '0');
      answer += SZ(cur_small_number) - SZ(v);

      if (new_len >= kLargeNumBound) {
        is_large_num = true;
        large_num_prefix = cur_small_number.substr(0, kLargeNumPrefix);
        num_len = new_len;
      }

    } else {
      if (!IsPrefix(v, large_num_prefix)) {
        num_len += (v < large_num_prefix);
        large_num_prefix = v;
      }

      answer += num_len - SZ(v);
    }
  }

  cout << answer << "\n";
}