Given an integer array of even length arr, return true if it is possible to reorder arr such that arr[2 * i + 1] = 2 * arr[2 * i] for every 0 <= i < len(arr) / 2, or false otherwise.
Examples
Example 1
Input: arr = [3,1,3,6]
Output: false
Example 2
Input: arr = [2,1,2,6]
Output: false
Example 3
Input: arr = [4,-2,2,-4]
Output: true
Explanation: We can take two groups, [-2,-4] and [2,4] to form [-2,-4,2,4] or [2,4,-2,-4].
Constraints
2 <= arr.length <= 3 * 104
arr.length is even.
-105 <= arr[i] <= 105
954. Array of Doubled Pairs
Medium
30 Points
Array
Hash Table
Greedy
Sorting
Given an integer array of even length arr, return true if it is possible to reorder arr such that arr[2 * i + 1] = 2 * arr[2 * i] for every 0 <= i < len(arr) / 2, or false otherwise.
Examples
Example 1
Input: arr = [3,1,3,6]
Output: false
Example 2
Input: arr = [2,1,2,6]
Output: false
Example 3
Input: arr = [4,-2,2,-4]
Output: true
Explanation: We can take two groups, [-2,-4] and [2,4] to form [-2,-4,2,4] or [2,4,-2,-4].
Constraints
2 <= arr.length <= 3 * 104
arr.length is even.
-105 <= arr[i] <= 105
Array of Doubled Pairs - Practice Coding | SlaveCode