Medium
You are given an integer array nums of size n and a positive integer k.
Divide the array into one or more arrays of size 3 satisfying the following conditions:
nums should be in exactly one array.k.Return a 2D array containing all the arrays. If it is impossible to satisfy the conditions, return an empty array. And if there are multiple answers, return any of them.
Example 1:
Input: nums = [1,3,4,8,7,9,3,5,1], k = 2
Output: [[1,1,3],[3,4,5],[7,8,9]]
Explanation: We can divide the array into the following arrays: [1,1,3], [3,4,5] and [7,8,9]. The difference between any two elements in each array is less than or equal to 2. Note that the order of elements is not important.
Example 2:
Input: nums = [1,3,3,2,7,3], k = 3
Output: []
Explanation: It is not possible to divide the array satisfying all the conditions.
Constraints:
n == nums.length1 <= n <= 105n is a multiple of 3.1 <= nums[i] <= 1051 <= k <= 105import java.util.Arrays;
public class Solution {
public int[][] divideArray(int[] nums, int k) {
Arrays.sort(nums);
int n = nums.length;
int triplets = n / 3;
int[][] result = new int[triplets][];
for (int i = 0, j = 0; i < n; i += 3, j++) {
int first = nums[i];
int third = nums[i + 2];
if (third - first > k) {
return new int[0][];
}
result[j] = new int[] {first, nums[i + 1], third};
}
return result;
}
}