Unique Number of Occurrences

Given an array of integers arr, return 1 if the number of occurrences of each value in the array is unique or 0 otherwise.

Input Format:

First parameter: an integer N, size of the array.

Second parameter: an array arr.

Output Format:

Return the number.

Example 1:

Input:
6
1 2 2 1 1 3
Output: 
1
Explanation: The value 1 has 3 occurrences, 2 has 2 and 3 has 1. No two values have the same number of occurrences.

Example 2:

Input:
2
1 2
Output: 
0

Example 3:

Input: 
10
-3 0 1 -3 1 1 1 -3 10 0
Output: 
1

Constraints:

• 1 <= arr.length <= 1000
• -1000 <= arr[i] <= 1000
• Expected Time Complexity: O(n)
• Expected Space Complexity: O(n)