368. Largest Divisible Subset

解题思路：

1. 用动态规划得到dp[i] represents the largest divisible subset numbers.

代码：
class Solution {
public List<Integer> largestDivisibleSubset(int[] nums) {

    List<Integer> res = new ArrayList<>();
    if(nums == null || nums.length == 0) return res;
    int len = nums.length;
    int[] dp = new int[len];
    Arrays.fill(dp, 1);
    Arrays.sort(nums);
    for(int i = 1; i < len; i++){
        for(int j = i - 1; j >= 0; j--){
            if(nums[i] % nums[j] == 0){
                dp[i] = Math.max(dp[i], dp[j]  + 1);
            }
        }
    }
    
    int maxIndex = 0;
    for(int i = 1; i < len; i++){
        maxIndex = dp[i] > dp[maxIndex] ? i : maxIndex;
    }
    
    int temp = nums[maxIndex];
    int curDp = dp[maxIndex];
    for(int i = maxIndex; i >= 0; i--){
        if(temp % nums[i] == 0 && dp[i] == curDp){
            res.add(nums[i]);
            temp = nums[i];
            curDp--;
        }
    }
    return res;
}

}