func main()
	var S: []char :: cui@input()
	for i(0, ^S - 1)
		switch(S[i])
		case 'A' to 'Z'
			do cui@print([S[i]].lower())
		case 'a' to 'z'
			do cui@print([S[i]].upper())
		end switch
	end for
	do cui@print("\n")
end func