#! ruby
# Try yukicoder
# author: Leornadone @ NEETSDKASU

S = gets.chomp

count = 0
i = 0

S.each_char do |c|
	if "KUROI"[i] == c || "?" == c
		i += 1
		if i == 5
			count += 1
			i = 0
		end
	end
end

puts count