def decrypt(string):
	i=0
	translated=''
	for char in string:
		hax=ord(char)
		hax=hax-i
		translated=translated+chr(hax)
		i=i+1
	print translated


def encrypt(string):
	i=0
	translated=''
	for char in string:
		hax=ord(char)
		hax=hax+i
		translated=translated+chr(hax)
		i=i+1
	print translated