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
#include <iostream>

using namespace std;

int main() {
    ios::sync_with_stdio(false);
    int n,x,y;
    int max = 201718;
    int tab[max+1];
    for(int i = 0; i <= max; i++){
        tab[i] = 0;
    }
    cin >> n;
    for(int i = 0; i < n; i++){
        cin >> x;
        tab[x]++;
    }
    y = 0;
    for(int i = 0; i < max; i++){
        if(tab[i] > 0){
            y = i;
        }
        tab[i+1] += tab[i]/2;
    }
    if(tab[max] > 0){
        y = max;
    }
    x = tab[y];
    while(x > 1){
        x /= 2;
        y++;
    }
    cout << y;
    return 0;
}