n = int(input())

numlist = []
flag = 0

for i in range(n):
    num = input()
    
    if " " in num:
        print('"assert"')
        flag = 1
        break
    else:
        numlist.append(int(num))
if flag:exit()
i = 0
l = []

l.append(numlist[0]+numlist[1])
l.append(numlist[1]+numlist[2])
l.append(numlist[0]+numlist[2])

l = list(set(l))
l.sort(reverse=True)

for i in l:
    i = str(i)

print(l[1])