s = gets.chop
maxcount = 0
wstart = 0
wend = 0
tmp = 0
i = 0

while i < s.size
	if s[i] == "ｗ"
		tmp += 1
		if maxcount < tmp
			maxcount = tmp
			wend = i - 1
		end
	else
		wsrart = i
		tmp = 0
	end
	i += 1
end

puts s[wstart,wend]