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Shuffle an Array

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Descritption

https://leetcode.com/problems/shuffle-an-array/description/

Solution

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class Solution {
public:
    Solution(vector<int> nums) {
        current = nums;
        origin = nums;
    }
    
    /** Resets the array to its original configuration and return it. */
    vector<int> reset() {
        return origin;
    }
    
    /** Returns a random shuffling of the array. */
    vector<int> shuffle() {
        vector<int> ret;
        int size = this->origin.size();
        while(size > 0) {
            int randomIndex = rand() % size;
            ret.push_back(current[randomIndex]);
            swap(current, randomIndex, size - 1);
            size -= 1;
        }
        return ret;
    }
    
    void swap(vector<int>& vec, int left, int right) {
        int temp = vec[left];
        vec[left] = vec[right];
        vec[right] = temp;
    }
private:
    vector<int> origin;
    vector<int> current;
};

/**
 * 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();
 */