Find a Pair with Given Sum

You are given an integer n representing the number of elements in an array, followed by an integer K. Then, an array of n integers is provided.

Your task is to determine if there exist two distinct integers in the array whose sum is equal to K. If such a pair exists, output YES; otherwise, output NO.

The solution should read input from standard input (stdin) and write the answer to standard output (stdout).

Note: Two integers are considered distinct if they come from different positions in the array, even if they have the same value.

Mathematical formulation:

Given an array \(A = [a_1, a_2, \dots, a_n]\) and an integer \(K\), determine if there exist indices \(i\) and \(j\) with \(i \neq j\) such that:

\[ a_i + a_j = K \]

inputFormat

The first line of input contains two integers n and K separated by a space, where:

• n is the number of elements in the array.
• K is the target sum.

The second line contains n integers separated by spaces representing the array elements.

outputFormat

Print YES if there exists at least one pair of distinct integers whose sum equals K, otherwise print NO. The output should be written to standard output.

## sample

5 6
1 3 4 2 5

YES