Welcome to the contest! This task will prepare you for the other tasks in this contest. For this task, please print out whether there are duplicate elements in the array ~a~.

Input Specification

The first line will contain the integer ~N~ ~(1 \le N \le 10^5)~.

The second line will contain ~N~ integers, ~a_i~ ~(0 \le a_i \le 10^9)~, the elements of the array.

Output Specification

Print YES, if there are duplicate elements, and NO otherwise.

Sample Input 1

5
1 3 9 2 0

Sample Output 1

NO

Sample Input 2

4
1 2 3 2

Sample Output 2

YES