 # Unique Number of Occurrences Lab

Easy
2
30.6% Acceptance

This lab focuses on testing your ability to implement a function that checks the unique number of occurrences in an array of integers. The primary goal of the lab is to return `true` if the number of occurrences of each value in the given array is unique or `false` otherwise.

In this lab, you'll be provided with an initial setup that includes a function called `uniqueOccurrences(arr)` which takes an array of integers as input.

Your task is to implement and export the `uniqueOccurrences` function that fulfills the following requirements:

• The input `arr` is an array of integers, with the length between 1 to 1000, and values ranging from -1000 to 1000.
• The function should return a boolean value based on the uniqueness of occurrences of each integer in the array.

## Examples

Example 1:

``````const arr1 = [1, 2, 2, 1, 1, 3];
const output1 = uniqueOccurrences(arr1);
console.log(output1); // true``````

Explanation: The value 1 occurs 3 times, the value 2 occurs 2 times, and the value 3 occurs 1 time. No two values have the same number of occurrences.

Example 2:

``````const arr2 = [1, 2];
const output2 = uniqueOccurrences(arr2);
console.log(output2); // false``````

Example 3:

``````const arr3 = [-3, 0, 1, -3, 1, 1, 1, -3, 10, 0];
const output3 = uniqueOccurrences(arr3);
console.log(output3); // true``````

## Challenges

1. Implement the `uniqueOccurrences` function and export it properly so that it can be imported in the evaluation script.
2. Ensure that your implementation of `uniqueOccurrences` fulfills the requirements mentioned in the given examples and returns the expected output for those examples.

While implementing your solution, make sure that your code is bug-free, properly tested, and follows best practices.

Good luck!