Problem: You are given N integers A_1, A_2, ..., A_N.

Consider the sums of all non-empty subsequences of A. There are 2^N - 1 such sums, an odd number.

Let the list of these sums in non-decreasing order be S_1, S_2, ..., S_{2^N - 1}.

Find the median of this list, S_{2^{N-1}}.

Constraints

* 1 \leq N \leq 2000
* 1 \leq A_i \leq 2000
* All input values are integers.

Input

Input is given from Standard Input in the following format:


N
A_1 A_2 ... A_N


Output

Print the median of the sorted list of the sums of all non-empty subsequences of A.

Examples

Input

3
1 2 1


Output

2


Input

1
58


Output

58

Solution (in CPP):

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

const int maxn = 2005;
bitset<maxn*maxn/2> f;
int n, a, sum, cur;

int main() {
	scanf("%d", &n); f[0] = 1;
	for (int i=1; i<=n; i++) {
		scanf("%d", &a); sum += a;
		f = f | (f << a);
	}
	cur = (sum + 1) / 2;
	while (!f[cur]) cur++;
	printf("%d\n", cur);
	return 0;
}