import sys
def solve():
    input = list(map(int,sys.stdin.read().split()))
    n = input[0]
    a = input[1:n+1]
    t1,t2 = 0,0
    for num in a:
        if t1 <= t2:
            t1 += num
        else:
            t2 += num
    print(max(t1,t2))

solve()