# 1885. Count Pairs in Two Arrays

<https://leetcode.com/problems/count-pairs-in-two-arrays>

## Description

Given two integer arrays `nums1` and `nums2` of length `n`, count the pairs of indices `(i, j)` such that `i < j` and `nums1[i] + nums1[j] > nums2[i] + nums2[j]`.

Return *the **number of pairs** satisfying the condition.*

**Example 1:**

```
**Input:** nums1 = [2,1,2,1], nums2 = [1,2,1,2]
**Output:** 1
**Explanation**: The pairs satisfying the condition are:
- (0, 2) where 2 + 2 > 1 + 1.
```

**Example 2:**

```
**Input:** nums1 = [1,10,6,2], nums2 = [1,4,1,5]
**Output:** 5
**Explanation**: The pairs satisfying the condition are:
- (0, 1) where 1 + 10 > 1 + 4.
- (0, 2) where 1 + 6 > 1 + 1.
- (1, 2) where 10 + 6 > 4 + 1.
- (1, 3) where 10 + 2 > 4 + 5.
- (2, 3) where 6 + 2 > 1 + 5.
```

**Constraints:**

* `n == nums1.length == nums2.length`
* `1 <= n <= 105`
* `1 <= nums1[i], nums2[i] <= 105`

## ac

```java
```
