368. Largest Divisible Subset

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:

nums: [1,2,3]Result: [1,2] (of course, [1,3] will also be ok)

Example 2:

nums: [1,2,4,8]Result: [1,2,4,8]

找出一串能接三连四的被整除。

其实就是排序，然后一次计算数组里的数的值，存到dp中，作为后面的数的计算的依据，然后整个把得到的结果根据dp保存的值一起输入到数组里就好了。

class Solution {public:    vector<int> largestDivisibleSubset(vector<int>& nums) {        sort(nums.begin(), nums.end());        int len = nums.size();        if(len <=1){            return nums;        }        vector<int> dp(len, 1);        int max=0;        int count=0;        for(int i=1; i<len; i++){            for(int j=i-1;j>=0;j--){                if(nums[i] % nums[j] == 0){                    dp[i] = std::max( dp[i], dp[j] + 1);                    if(max < dp[i]){                        max = dp[i];                        count = i;                    }                }            }        }        vector<int> res;        int tmp = dp[count]-1;        for(int i=0;i<=count;i++){            if(nums[count]%nums[i] == 0 && dp[i]==dp[count]-tmp){                res.push_back(nums[i]);                tmp--;            }        }        return res;    }};