384. 打乱数组

384. 打乱数组

Fisher–Yates shuffle - Wikipedia

class Solution {
public:
    Solution(vector<int>& nums) : origin(nums), n(origin.size()) {

    }
    
    vector<int> reset() {
        return origin;
    }
    
    vector<int> shuffle() {
        vector<int> shuffled(origin);
        for(int i = 0; i < n; ++i)
        {
            int j = rand() % (n - i) + i;
            swap(shuffled[i], shuffled[j]);
        }
        return shuffled;
    }
private:
    vector<int> origin;
    int n;
};

/**
 * Your Solution object will be instantiated and called as such:
 * Solution* obj = new Solution(nums);
 * vector<int> param_1 = obj->reset();
 * vector<int> param_2 = obj->shuffle();
 */