1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
#include <iostream>
using namespace std;


int main() {
	int n, q;
	int arr[203000] = {0};
	cin>>n;
	for (int i = 0; i < n; ++i) {
		cin>>q;
		arr[q]++;
	}
	int res = 0;
	for (int i = 0; i < 202200; ++i) {
		if (arr[i] > 0) {
			res = i;
		}
		arr[i + 1] += arr[i] / 2;
	}
	cout<<res<<endl;
	return 0;
}