n = int(input())
a = []
for i in range(n):
    tmp = input()
    if " " in tmp:
        print("assert")
        print()
        exit()
    a.append(int(tmp))

li = [0]*3
li[0] = a[0]+a[1]
li[1] = a[0]+a[2]
li[2] = a[1]+a[2]
li = set(li)
li = list(li)
li.sort(reverse=True)
print(li[1])