2426 - Number of Pairs Satisfying Inequality\.

Hard

You are given two 0-indexed integer arrays nums1 and nums2, each of size n, and an integer diff. Find the number of pairs (i, j) such that:

• 0 <= i < j <= n - 1 and

• nums1[i] - nums1[j] <= nums2[i] - nums2[j] + diff.

Return the number of pairs that satisfy the conditions.

Example 1:

Input: nums1 = 3,2,5, nums2 = 2,2,1, diff = 1

Output: 3

Explanation:

There are 3 pairs that satisfy the conditions:

• i = 0, j = 1: 3 - 2 <= 2 - 2 + 1. Since i < j and 1 <= 1, this pair satisfies the conditions.

• i = 0, j = 2: 3 - 5 <= 2 - 1 + 1. Since i < j and -2 <= 2, this pair satisfies the conditions.

• i = 1, j = 2: 2 - 5 <= 2 - 1 + 1. Since i < j and -3 <= 2, this pair satisfies the conditions.

Therefore, we return 3.

Example 2:

Input: nums1 = 3,-1, nums2 = -2,2, diff = -1

Output: 0

Explanation:

Since there does not exist any pair that satisfies the conditions, we return 0.

Constraints:

• n == nums1.length == nums2.length

• <code>2 <= n <= 10⁵</code>

• <code>-10⁴<= nums1i, nums2i<= 10⁴</code>

• <code>-10⁴<= diff <= 10⁴</code>