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#include<bits/stdc++.h>
#define rep(i,k,n) for(ll i= (ll) k;i< (ll) n;i++)
#define all(v) (v).begin(), (v).end()
#define SZ(v) (ll)((v).size())
#define pb push_back
#define ft first
#define sd second
typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
const long long INF = 1e18L + 1;
const int IINF = 1e9 + 1;

using namespace std;

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...);
}

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

int main()
{
#ifndef LOCAL
	ios_base::sync_with_stdio(0);
    cin.tie(0);
#endif
	ll n; cin >> n;
	ll prv = 0, res = 0;
	rep(_, 0, n){
		ll a; cin >> a;
		ll tp = 1ll;
		while((a + 1) * tp - 1 <= prv){
			tp *= 10;
			res++;
		}
		if(a * tp > prv){
			prv = a * tp;
		} else{
			prv++;
		}
	}
	cout << res << "\n";
    return 0;
}