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Java-based LeetCode algorithm problem solutions, regularly updated

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package g1601_1700.s1652_defuse_the_bomb;

// #Easy #Array #2022_04_22_Time_0_ms_(100.00%)_Space_42.5_MB_(72.00%)

/**
 * 1652 - Defuse the Bomb\.
 *
 * Easy
 *
 * You have a bomb to defuse, and your time is running out! Your informer will provide you with a **circular** array `code` of length of `n` and a key `k`.
 *
 * To decrypt the code, you must replace every number. All the numbers are replaced **simultaneously**.
 *
 * *   If `k > 0`, replace the i^th number with the sum of the **next** `k` numbers.
 * *   If `k < 0`, replace the i^th number with the sum of the **previous** `k` numbers.
 * *   If `k == 0`, replace the i^th number with `0`.
 *
 * As `code` is circular, the next element of `code[n-1]` is `code[0]`, and the previous element of `code[0]` is `code[n-1]`.
 *
 * Given the **circular** array `code` and an integer key `k`, return _the decrypted code to defuse the bomb_!
 *
 * **Example 1:**
 *
 * **Input:** code = [5,7,1,4], k = 3
 *
 * **Output:** [12,10,16,13]
 *
 * **Explanation:** Each number is replaced by the sum of the next 3 numbers. The decrypted code is [7+1+4, 1+4+5, 4+5+7, 5+7+1]. Notice that the numbers wrap around.
 *
 * **Example 2:**
 *
 * **Input:** code = [1,2,3,4], k = 0
 *
 * **Output:** [0,0,0,0]
 *
 * **Explanation:** When k is zero, the numbers are replaced by 0.
 *
 * **Example 3:**
 *
 * **Input:** code = [2,4,9,3], k = -2
 *
 * **Output:** [12,5,6,13]
 *
 * **Explanation:** The decrypted code is [3+9, 2+3, 4+2, 9+4]. Notice that the numbers wrap around again. If k is negative, the sum is of the **previous** numbers.
 *
 * **Constraints:**
 *
 * *   `n == code.length`
 * *   `1 <= n <= 100`
 * *   `1 <= code[i] <= 100`
 * *   `-(n - 1) <= k <= n - 1`
**/
public class Solution {
    public int[] decrypt(int[] code, int k) {
        int[] result = new int[code.length];
        int len = code.length;
        if (k == 0) {
            for (int i = 0; i < code.length; i++) {
                result[i] = 0;
            }
        } else if (k > 0) {
            int kSum = 0;
            for (int i = 1; i <= k; i++) {
                kSum += code[i];
            }
            result[0] = kSum;
            for (int i = 1; i < len; i++) {
                kSum -= code[i];
                kSum += code[(i + k) % len];
                result[i] = kSum;
            }
        } else {
            int kSum = 0;
            int kVal = Math.abs(k);
            for (int i = len - 1; i >= len - kVal; i--) {
                kSum += code[i];
            }
            result[0] = kSum;
            for (int i = 1; i < len; i++) {
                kSum -= code[(len - kVal + i - 1) % len];
                kSum += code[i - 1];
                result[i] = kSum;
            }
        }
        return result;
    }
}