Pair Sum Problem

You are given an array of integers and a target integer. Your task is to determine whether there exists a pair of distinct elements in the array whose sum is equal to the target. In other words, you need to check if there exist indices $i$ and $j$ such that $i \neq j$ and $$a_i + a_j = \text{target}.$$ If such a pair exists, print Yes; otherwise, print No.

Note: The array may be empty or contain negative numbers.

inputFormat

The first line of input contains an integer $n$ representing the number of elements in the array. The second line contains $n$ space-separated integers representing the array elements. The third line contains an integer representing the target sum.

outputFormat

Output a single line with Yes if there exists a pair of distinct elements whose sum is equal to the target, and No otherwise.## sample

5
2 7 11 15 3
9

Yes