1497. Check If Array Pairs Are Divisible by k Medium

1/**
2 * [1497] Check If Array Pairs Are Divisible by k
3 *
4 * Given an array of integers arr of even length n and an integer k.
5 * We want to divide the array into exactly n / 2 pairs such that the sum of each pair is divisible by k.
6 * Return true If you can find a way to do that or false otherwise.
7 *  
8 * Example 1:
9 * 
10 * Input: arr = [1,2,3,4,5,10,6,7,8,9], k = 5
11 * Output: true
12 * Explanation: Pairs are (1,9),(2,8),(3,7),(4,6) and (5,10).
13 * 
14 * Example 2:
15 * 
16 * Input: arr = [1,2,3,4,5,6], k = 7
17 * Output: true
18 * Explanation: Pairs are (1,6),(2,5) and(3,4).
19 * 
20 * Example 3:
21 * 
22 * Input: arr = [1,2,3,4,5,6], k = 10
23 * Output: false
24 * 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.
25 * 
26 *  
27 * Constraints:
28 * 
29 * 	arr.length == n
30 * 	1 <= n <= 10^5
31 * 	n is even.
32 * 	-10^9 <= arr[i] <= 10^9
33 * 	1 <= k <= 10^5
34 * 
35 */
36pub struct Solution {}
37
38// problem: https://leetcode.com/problems/check-if-array-pairs-are-divisible-by-k/
39// discuss: https://leetcode.com/problems/check-if-array-pairs-are-divisible-by-k/discuss/?currentPage=1&orderBy=most_votes&query=
40
41// submission codes start here
42
43impl Solution {
44    pub fn can_arrange(arr: Vec<i32>, k: i32) -> bool {
45        false
46    }
47}
48
49// submission codes end
50
51#[cfg(test)]
52mod tests {
53    use super::*;
54
55    #[test]
56    fn test_1497() {
57    }
58}
59