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<bitset>
#include<cstdio>
#include<cstring>
#include<algorithm>
#define N 2005
using namespace std;
bitset<N*N>f;
int main(){
	int n,x,sum=0;
	scanf("%d",&n);
	f[0]=1;
	for(int i=1;i<=n;++i){
		scanf("%d",&x);
		f|=(f<<x),sum+=x;
	}
	for(int i=(sum+1)/2;i<=sum;++i)
		if(f[i])  return printf("%d",i),0;
	return 0;
}