Pair with Sum

You are given an array of N integers and an integer K. Your task is to determine whether there exist two distinct indices i and j such that:

$$A[i] + A[j] = K$$

If such a pair exists, print YES; otherwise, print NO. The array may contain negative numbers and duplicate values.

inputFormat

The first line contains two integers N and K, where N is the number of elements in the array and K is the target sum.

The second line contains N space-separated integers representing the array A.

You should read input from stdin.

outputFormat

Print a single line to stdout containing YES if there exists a pair of distinct indices i and j such that A[i] + A[j] = K, or NO otherwise.

## sample

4 7
1 2 3 4

YES

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