1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
#include<iostream>
#include<sstream>
using namespace std;

string numberToString(int number){
	ostringstream ss;
	ss << number;
	return ss.str();
}

string stringNumPlusOne(string s, int pos){
	bool added = false;
	s = s.substr(pos);
	for(int i=s.size()-1; i>=0; i--){
		if(s[i] != '9'){
			s[i] = char(s[i] + 1);
			added = true;
			break;
		} else{
			s[i] = '0';
		}
	}
	if(!added){
		s += '0';
	}
	return s;
}

int main(){
	int n, a;
	cin >> n;

	n--;
	cin >> a;

	long long changes = 0;
	string last_number = numberToString(a);

	while(n--){
		int a;
		cin >> a;
		string current_number = numberToString(a);

		int cns = current_number.size(), lns = last_number.size();

		if(cns == lns){
			if(current_number <= last_number){
				last_number = current_number + '0';
				changes += 1;
			} else {
				last_number = current_number;
			}
		} else if(cns < lns) {
			int string_compare = last_number.compare(0, cns, current_number);
			if(string_compare == 0){
				last_number = current_number + stringNumPlusOne(last_number, cns);
				changes += last_number.size() - cns;
			} else if(string_compare > 0){
				changes += lns - cns + 1;
				current_number.append(lns-cns+1, '0');
				last_number = current_number;
			} else {
				changes += lns - cns;
				current_number.append(lns-cns, '0');
				last_number = current_number;
			}
		} else{
			last_number = current_number;
		}
	}
	cout << changes;
}