# Write a Program to Find the Distinct Difference Array

# 2670. Find the Distinct Difference Array

You are given a 0-indexed array nums of length n.

The distinct difference array of nums is an array diff of length n such that diff[i] is equal to the number of distinct elements in the suffix nums[i + 1, …, n – 1] subtracted from the number of distinct elements in the prefix nums[0, …, i].

Return the distinct difference array of nums.

Note that nums[i, …, j] denotes the subarray of nums starting at index i and ending at index j inclusive. Particularly, if i > j then nums[i, …, j] denotes an empty subarray.

```### Example 1:
```
Input: nums = [1,2,3,4,5]
Output: [-3,-1,1,3,5]
Explanation: For index i = 0, there is 1 element in the prefix and 4 distinct elements in the suffix. Thus, diff[0] = 1 - 4 = -3.
For index i = 1, there are 2 distinct elements in the prefix and 3 distinct elements in the suffix. Thus, diff[1] = 2 - 3 = -1.
For index i = 2, there are 3 distinct elements in the prefix and 2 distinct elements in the suffix. Thus, diff[2] = 3 - 2 = 1.
For index i = 3, there are 4 distinct elements in the prefix and 1 distinct element in the suffix. Thus, diff[3] = 4 - 1 = 3.
For index i = 4, there are 5 distinct elements in the prefix and no elements in the suffix. Thus, diff[4] = 5 - 0 = 5.
```
```
```### Example 2:
```
Input: nums = [3,2,3,4,2]
Output: [-2,-1,0,2,3]
Explanation: For index i = 0, there is 1 element in the prefix and 3 distinct elements in the suffix. Thus, diff[0] = 1 - 3 = -2.
For index i = 1, there are 2 distinct elements in the prefix and 3 distinct elements in the suffix. Thus, diff[1] = 2 - 3 = -1.
For index i = 2, there are 2 distinct elements in the prefix and 2 distinct elements in the suffix. Thus, diff[2] = 2 - 2 = 0.
For index i = 3, there are 3 distinct elements in the prefix and 1 distinct element in the suffix. Thus, diff[3] = 3 - 1 = 2.
For index i = 4, there are 3 distinct elements in the prefix and no elements in the suffix. Thus, diff[4] = 3 - 0 = 3.
```
```
```Constraints:
```
1 <= n == nums.length <= 50
1 <= nums[i] <= 50
```
```
```/**
* @param {number[]} nums
* @return {number[]}
*/
const distinctDifferenceArray = function(nums) {
const out = [];
for(let i = 0; i < nums.length; i ++) {
const first = new Set(nums.slice(0, i+1));
const last = new Set(nums.slice(i+1));
out.push(first.size - last.size);
}
return out;
};

```