Dsa
Two Pointers
Easy
Unique Pair Count
You are given a sorted array of integers. Your task is to count the number of unique pairs (i, j) such that i < j and nums[i] + nums[j] = target. Each pair (i, j) must be counted only once regardless of their order.
Input:
- The first line contains an integer n (1 <= n <= 1000) - the length of the array.
- The second line contains n unique integers nums[i] sorted in non-decreasing order.
- The third line contains an integer target.
Output:
- Return the count of unique pairs that sum up to the target.
Example:
Input:
5
1 2 3 4 5
6
Output:
2
The pairs are (1, 5) and (2, 4).
Key concepts
two_pointerssortarray
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