import sys
import copy

sys.setrecursionlimit(9876543)

quant = int(input())

list = []
rm = []


def pwr(m):

    for n in range(1, m+1):

        melh = -1

    for k in range(j):

    	num1 = list[k] + rm[j-(w+1)]

            if melh < num1:

    		        melh = list[k] + rm[j-(w+1)]

                rm[j] = melh

        return rm[m]


while(quant!=0):

    list = []

    rm = [-1 for i in range(quant+15)]

    rm[0] = 0

    for m in range(quant):

        list.append(int(input()))


print(pwr(quant))
quant = int(input())