# Tower Of Hanoi - Problem
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# Tower of Hanoi is a mathematical puzzle where we have three rods and n disks. The objective of the puzzle is to move all disks from source rod to destination rod using third rod (say auxiliary). The rules are :
# 1) Only one disk can be moved at a time.
# 2) A disk can be moved only if it is on the top of a rod.
# 3) No disk can be placed on the top of a smaller disk.
# Print the steps required to move n disks from source rod to destination rod.
# Source Rod is named as 'a', auxiliary rod as 'b' and destination rod as 'c'.
# Input Format :
# Integer n
# Output Format :
# Steps in different lines (in one line print source and destination rod name separated by space)
# Constraints :
# 0 <= n <= 20
# Sample Input 1 :
# 2
# Sample Output 1 :
# a b
# a c
# b c
# Sample Input 2 :
# 3
# Sample Output 2 :
# a c
# a b
# c b
# a c
# b a
# b c
# a c

def towerofhanoi(n, source, aux, dest):
    if n==1:
        print(source, dest)
        return
    towerofhanoi(n-1, source,dest,aux)
    print(source,dest)
    towerofhanoi(n-1, aux, source,dest)
    

n=int(input())
if n != 0:
	towerofhanoi(n, 'a', 'b', 'c')
