Watch 10 video solutions for Check If Array Pairs Are Divisible by k, a medium level problem involving Array, Hash Table, Counting. This walkthrough by NeetCodeIO has 23,675 views views. Want to try solving it yourself? Practice on FleetCode or read the detailed text solution.
Given an array of integers arr of even length n and an integer k.
We want to divide the array into exactly n / 2 pairs such that the sum of each pair is divisible by k.
Return true If you can find a way to do that or false otherwise.
Example 1:
Input: arr = [1,2,3,4,5,10,6,7,8,9], k = 5 Output: true Explanation: Pairs are (1,9),(2,8),(3,7),(4,6) and (5,10).
Example 2:
Input: arr = [1,2,3,4,5,6], k = 7 Output: true Explanation: Pairs are (1,6),(2,5) and(3,4).
Example 3:
Input: arr = [1,2,3,4,5,6], k = 10 Output: false Explanation: You can try all possible pairs to see that there is no way to divide arr into 3 pairs each with sum divisible by 10.
Constraints:
arr.length == n1 <= n <= 105n is even.-109 <= arr[i] <= 1091 <= k <= 105