368. Largest Divisible Subset — LeetCode

Given a set of distinct positive integers, find the largest subset such that every pair (Si, Sj) of elements in this subset satisfies:

Si % Sj = 0 or Sj % Si = 0.

If there are multiple solutions, return any subset is fine.

Example 1:

Input: [1,2,3]
Output: [1,2] (of course, [1,3] will also be ok)

Example 2:

Input: [1,2,4,8]
Output: [1,2,4,8]

Here is my solution:

class Solution {
    public List<Integer> largestDivisibleSubset(int[] nums) {
        List<Integer> result = new ArrayList<>();
        Arrays.sort(nums);
        
        int dp[] = new int[nums.length];
        int index[] = new int[nums.length];
        Arrays.fill(dp, 1);
        Arrays.fill(index, -1);
        int maxSize = 0, maxIndex = -1;
        
        for(int i=0; i<nums.length;i++) {
            for(int j=i-1; j>=0;j--) {
                if(nums[i] %nums[j] == 0 && dp[j] + 1 > dp[i]) {
                    dp[i] = dp[j] + 1;
                    index[i] = j;
                }
            }
            if (maxSize<dp[i]) {
                maxSize = dp[i];
                maxIndex = i;
            }
        }
        
        int i = maxIndex;
        while(i>=0) {
            result.add(nums[i]);
            i=index[i];
        }
        
        return result;
    }
}

You can view full explanation on my YouTube channel. Here is the link