All you have to do is implement the following algorithm ,which is a very popular compression technique.

 1.You are given an input string A. (For eg. ababc )

 2.Find all the rotations of A (In this case, it is ababc,babca,abcab,bcaba,cabab)

 •	Now sort them (After sorting, we have ababc,abcab,babca,bcaba,cabab)
 •	Then arrange them as follows: 
	ababc 
	abcab 
	babca 	
bcaba 
	cabab 
•	Now pick out the last column. It is ‘cbaab’. It is the result of this algorithm
•	Also observe that the 1st row has the original string.(Use 1 indexing) 

 Now, for this problem, you are given the output and the row number that has the original string.
 For the above example , it is ‘cbaab’ and 1. 
 Given these 2 parameters, you just need to decode it. (ie.,find the original string.) 

 

Input:

 Each test case has 2 lines. 

1st line – An integer R that represents the row that contains the original string.

 2nd line - A string that represents the output of the above algorithm.  (Length of string <=2000) (All characters are lower case).
 The input is terminated with R=-1.
 
 Output:

 The original string. 

 Sample Input:

 1 
cbaab 
3 
mnoag
 -1 

Sample Output:

 ababc
 mango