Given an array of integers arr, return trueif the number of occurrences of each value in the array is unique orfalseotherwise.
Example 1:
1
2
3
Input: arr = [1,2,2,1,1,3]
Output: true
Explanation: The value 1 has 3 occurrences, 2 has 2 and 3 has 1. No two values have the same number of occurrences.
By using the map container to record the number of occurrences of each number, and then using the set container to record different occurrences, the size of the map and set can be compared to determine whether they are unique occurrences.
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