-- yukicoder My Practice
-- author: Leonardone @ NEETSDKASU
n = io.read()
gi = io.read():gmatch('%d+')
mx = 0
ans = 0
for i = 1, n do
v = tonumber(gi())
if v > mx then
mx = v
elseif v > ans then
ans = v
end
end
print(ans)
LS0geXVraWNvZGVyIE15IFByYWN0aWNlCi0tIGF1dGhvcjogTGVvbmFyZG9uZSBAIE5FRVRTREtBU1UKCm4gPSBpby5yZWFkKCkKCmdpID0gaW8ucmVhZCgpOmdtYXRjaCgnJWQrJykKCm14ID0gMAphbnMgPSAwCgpmb3IgaSA9IDEsIG4gZG8KCXYgPSB0b251bWJlcihnaSgpKQoJaWYgdiA+IG14IHRoZW4KCQlteCA9IHYKCWVsc2VpZiB2ID4gYW5zIHRoZW4KCQlhbnMgPSB2CgllbmQKZW5kCgpwcmludChhbnMp