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/************************************************************ JAVA ************************************************/
//Approach-(simple remainder maths)
//T.C : O(n)
//S.C : O(k)
class Solution {
    public boolean canArrange(int[] arr, int k) {
        int[] mp = new int[k];  // Array to store remainders frequency

        // Calculate the remainder frequencies
        for (int num : arr) {
            int rem = (num % k + k) % k;  // Handle negative remainders
            mp[rem]++;
        }

        // Check if the frequency of numbers with 0 remainder is even
        if (mp[0] % 2 != 0) {
            return false;
        }

        // Check if each remainder has a complement remainder with matching frequency
        for (int rem = 1; rem <= k / 2; rem++) {
            int counterHalf = k - rem;
            if (mp[counterHalf] != mp[rem]) {
                return false;
            }
        }

        return true;
    }
}