def mp(n, r):
    from functools import lru_cache

    p = [0] * (n + 1)
    for i in range(n):
        p[i + 1] = p[i] + r[i]

    @lru_cache(None)
    def f(l, r):
        if l == r:
            return 0
        mX = 0
        for m in range(l, r):
            s1, s2 = p[m + 1] - p[l], p[r + 1] - p[m + 1]
            if s1 > s2:
                mX = max(mX, f(m + 1, r) + s2)
            elif s1 < s2:
                mX = max(mX, f(l, m) + s1)
            else:
                mX = max(mX, f(m + 1, r) + s2, f(l, m) + s1)
        return mX

    print(f(0, n - 1))

n = int(input())
r = list(map(int, input().split()))
mp(n, r)

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