#include <iostream>
#include <cmath>
#include <algorithm>
using namespace std;
int n, k, a[500006], c;
int main() {
    cin >> n >> k;
    c = 1;
    int i, j;
    for (i = 1; i <= n; i++) {
        scanf("%d", &a[i]);
    }
    for (i = 1; i < n; i++) {
        for (j = i + 1; j <= n; j++) {
            if (a[i] + a[j] == k) {
                c = 0;
                break;
            }
        }
        if (c == 0)
            break;
    }
    if (c == 0)
        cout << "Yes";
    else
        cout << "No";
}

/sandbox/1/a.cpp: In function 'int main()':
/sandbox/1/a.cpp:13:3: error: 'scanf' was not declared in this scope
   scanf("%d",&a[i]);
   ^~~~~
/sandbox/1/a.cpp:13:3: note: suggested alternative: 'wscanf'
   scanf("%d",&a[i]);
   ^~~~~
   wscanf