A rumor says two projects' combined marks equal exactly the passing threshold K — Tanvir must check if any such pair exists among all submitted marks. Read N integers and integer K. Print "YES" if any two DIFFERENT positions i≠j have a[i]+a[j]=K, else "NO". Aim for O(N) or O(N log N), not O(N^2), since N can be up to 10^5.
Input
First line N K, second line N integers.
Output
"YES" or "NO".
Constraints
1 ≤ N ≤ 10^5, |a_i|,|K| ≤ 10^9
Sample Input
5 9 2 7 4 1 5
Sample Output
YES
main.c
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