import sequtils, strutils
let
  n: int = stdin.readline.parseInt
  a: seq[int] = stdin.readline.split.map(parseInt)
var ans: string = "\"assert\""
if a.len == 1:
  let
    b, c: int = stdin.readline.parseInt
    d: array[3, int] = [a[0] + b, b + c, c + a[0]]
  var tmp = 0
  for i in d:
    if i != max(d):
      tmp = max(tmp, i)
  ans = $(tmp)
echo ans