Nick'S Check :
Difficulty Level : Easy
Submissions : 93
Asked In :
Marks :10
: 1 | : 0
Nick has been given a list of random numbers by his teacher. His task is to arrange all the numbers in increasing order, and check whether the numbers are consecutive or not. If all the numbers are consecutive, output "YES", otherwise output "NO".
Input
The first line consists of an integer $$$n$$$ $$$-$$$ the total number of integers given by the teacher $$$(1 \leq n \leq 10^6)$$$. The next line consists of $$$n$$$ space separated integers, $$$a_i$$$ $$$(1 \leq a_i \leq 10^9)$$$ the numbers of the array.
Output
Output a single word - "YES" if the marks are consecutive, "NO" otherwise.
Examples
Input
4 7 8 5 6
Output
YES
Input
4 10 8 9 8
Output
NO
Input
5 1 9 10 4 2
Output
NO
Note
Note that if two marks are the same, then they are not considered consecutive.
