func main()
	var s: []char :: cui@input()
	var n: int :: ^s
	
	var idxs: []int :: #[n]int
	for i(0, n - 1)
		do idxs[i] :: i
	end for
	
	var dic: dict<[]char, bool> :: #dict<[]char, bool>
	for id(0, 2 ^ (n - 1) - 1)
		var ns: []char :: #[n]char
		var ii: int :: id
		var mn: int :: 0
		var mx: int :: n - 1
		for i(0, n - 1)
			if(ii % 2 = 0)
				do ns[i] :: s[mn]
				do mn :+ 1
			else
				do ns[i] :: s[mx]
				do mx :- 1
			end if
			do ii :/ 2
		end for
		do dic.add(ns, true)
	end for
	var ans: int :: ^dic
	do cui@print("\{ans}\n")
	
	func nextPermutation(arr: []int): bool
		var len: int :: ^arr
		var left: int :: len - 2
		while(left >= 0 & arr[left] >= arr[left + 1])
			do left :- 1
		end while
		if(left < 0)
			ret false
		end if
		var right: int :: len - 1
		while(arr[left] >= arr[right])
			do right :- 1
		end while
		var tmp: int :: arr[left]
		do arr[left] :: arr[right]
		do arr[right] :: tmp
		do left :+ 1
		do right :: len - 1
		while(left < right)
			do tmp :: arr[left]
			do arr[left] :: arr[right]
			do arr[right] :: tmp
			do left :+ 1
			do right :- 1
		end while
		ret true
	end func
end func