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;
bitset<4000010> b;
int main(){
	long long n,p=0;
	scanf("%lld",&n);
	b[0]=1;
	long long m=n;
	while(m--){
		long long v;
		scanf("%lld",&v);
		b|=b<<v;
		p+=v;
	}
	long long ans=(1+p)/2;
	while(!b[ans])
		ans++;
	printf("%lld",ans);
}