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 PYTHON3):

Solution:
from math import ceil
N = int(input())
A = [int(a) for a in input().split()]

DP = 1
for a in A:
    DP |= DP << a

Shalf = ceil(sum(A)/2)
DP >>= Shalf
for i in range(N * max(A)):
    if DP & 1:
        print(Shalf + i)
        break
    DP >>= 1