1346. Check If N and Its Double Exist

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Given an array arr of integers, check if there exist two indices i and j such that :

Example 1:

Input: arr = [10,2,5,3]
Output: true
Explanation: For i = 0 and j = 2, arr[i] == 10 == 2 * 5 == 2 * arr[j]

Example 2:

Input: arr = [3,1,7,11]
Output: false
Explanation: There is no i and j that satisfy the conditions.

Constraints:

Hint 1

Loop from i = 0 to arr.length, maintaining in a hashTable the array elements from [0, i - 1].

Hint 2

On each step of the loop check if we have seen the element 2 * arr[i] so far.

Hint 3

Also check if we have seen arr[i] / 2 in case arr[i] % 2 == 0.