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#include <bits/stdc++.h>
using namespace std;

using i64 = long long;

int getLength(i64 x){
	if (!x) return 1;
	int res = 0;
	for (; x; x /= 10, ++res);
	return res;
}
i64 fpow(i64 a, int t){
	i64 r = 1;
	for (; t; t >>= 1, a *= a) if (t & 1) r *= a;
	return r;
}

i64 result;

static const int C = 17;
static const int C1 = 11, C2 = 6;
static int Error = fpow(10, C2) - 2;

struct bignum {
	int len;
	// case 1: len <= C
	i64 number;
	// case 2: len > C
	i64 prefix, suffix;
	// prefix contains first 10 digits, suffix contains no more than 6 digits
	void extend(i64 value){
		int g = getLength(value);
		if (++len <= C) {
			if (len < g) len = g;
			number = value * fpow(10, len - g);
		} else {
			prefix = value * fpow(10, C1 - g);
			suffix = 0;
		}
		result += len - g;
	}
	void append(i64 value){
		int g = getLength(value);
		if (g > len) return extend(value);
		if (len <= C) {
			i64 imax = (value + 1) * fpow(10, len - g) - 1;
			if (imax <= number) return extend(value); 
			i64 imin = value * fpow(10, len - g);
			if (imin > number) number = imin;
			else ++number;
		} else {
			assert(suffix <= Error);
			i64 imax = (value + 1) * fpow(10, C1 - g) - 1;
			if (imax < prefix) return extend(value);
			i64 imin = value * fpow(10, C1 - g);
			if (imin > prefix) {
				prefix = imin;
				suffix = 0;
			} else ++suffix;
		}
		result += len - g;
	}
} answer;

int n;

int main(){
	int i, a;
	scanf("%d", &n);
	answer.len = 1;
	for (i = 1; i <= n; ++i) scanf("%d", &a), answer.append(a); 
	printf("%lld\n", result);
}