Jolly Jumpers

This problem was from the book Programming Challenges.
Here is the description of the problem:

A sequence of n > 0 integers is called a jolly jumper if the absolute values of the
differences between successive elements take on all possible values 1 through n − 1. For
instance,

1 4 2 3

is a jolly jumper, because the absolute differences are 3, 2, and 1, respectively. The
definition implies that any sequence of a single integer is a jolly jumper. Write a program
to determine whether each of a number of sequences is a jolly jumper.

Input
Each line of input contains an integer n < 3, 000 followed by n integers representing the
sequence.

Output
For each line of input generate a line of output saying “Jolly” or “Not jolly”.

Sample Input
4 1 4 2 3
5 1 4 2 -1 6

Sample Output
Jolly
Not jolly


Here is the Solution in C#
Another Solution in Java

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