Sorted Pair Sum

**Description:** In a sorted array of n integers, decide whether two elements at DIFFERENT positions sum exactly to S. **Input:** Line 1: n S (2 <= n <= 200000, |S| <= 10^18). Line 2: n sorted integers (|a[i]| <= 10^9). **Output:** Print YES if such a pair exists, otherwise NO. **Example:** 5 9 / 1 2 4 7 11 -> YES (2 + 7).