PERMUT2 - Ambiguous Permutations

Some programming contest problems are really tricky: not only do they require a different output format from what you might have expected, but also the sample output does not show the difference. For an example, let us look at permutations.
A permutation of the integers 1 to n is an ordering of these integers. So the natural way to represent a permutation is to list the integers in this order. With n = 5, a permutation might look like 2, 3, 4, 5, 1.
However, there is another possibility of representing a permutation: You create a list of numbers where the i-th number is the position of the integer i in the permutation. Let us call this second possibility an inverse permutation. The inverse permutation for the sequence above is 5, 1, 2, 3, 4.
An ambiguous permutation is a permutation which cannot be distinguished from its inverse permutation. The permutation 1, 4, 3, 2 for example is ambiguous, because its inverse permutation is the same. To get rid of such annoying sample test cases, you have to write a program which detects if a given permutation is ambiguous or not.

Input Specification

The input contains several test cases.
The first line of each test case contains an integer n (1 ≤ n ≤ 100000). Then a permutation of the integers 1 to n follows in the next line. There is exactly one space character between consecutive integers. You can assume that every integer between 1 and n appears exactly once in the permutation.
The last test case is followed by a zero.

Output Specification

For each test case output whether the permutation is ambiguous or not. Adhere to the format shown in the sample output.

Sample Input

1 4 3 2
2 3 4 5 1

Sample Output

not ambiguous

hide comments
shantanu_sarin: 2017-01-01 14:49:55

irritating lang

kass_97: 2016-12-31 12:47:14

Unclear problem statement, still AC in 2nd 100th yeahh

sri: 2016-12-27 13:43:44

150th...., easy one though question is confused

shubham_cs_iet: 2016-12-11 18:29:21

spelling of ambiguous cost me 1 TLE. Don't know how....

soodan: 2016-12-11 17:29:36

AC in one go

codesok: 2016-12-03 15:13:26

Easiest Problem.
Problem statement looks confusing at first. Try understanding it. After that 2 min coding work :)

aronzx: 2016-11-02 14:31:26

Unclear problem statement! Took me more time to read and make sense of it than getting AC .

sak_sam: 2016-10-11 12:51:39

AC in one go :D

nikhil03: 2016-08-23 23:14:58

Easy question, AC in a go!!!
Try NOT to read it again and again if not getting the question.
Rather, read it after sometime.

Saif : 2016-08-22 19:55:35

@ragnerok Read the problem statement again ,you are already given a permutation

Added by:Adrian Kuegel
Time limit:10s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Languages:All except: NODEJS PERL 6
Resource:own problem, used in University of Ulm Local Contest 2005