-- 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)