# 384. Shuffle an Array

Shuffle a set of numbers without duplicates.
Example:

``````// Init an array with set 1, 2, and 3.
int[] nums = {1,2,3};
Solution solution = new Solution(nums);

// Shuffle the array [1,2,3] and return its result. Any permutation of [1,2,3] must equally likely to be returned.
solution.shuffle();

// Resets the array back to its original configuration [1,2,3].
solution.reset();

// Returns the random shuffling of array [1,2,3].
solution.shuffle();
``````

Solution:

``````class Solution {
public:
vector<int> v;
int size;
Solution(vector<int> nums) {
v = nums;
size = nums.size();
srand(time(0));
}

/** Resets the array to its original configuration and return it. */
vector<int> reset() {
return v;
}

/** Returns a random shuffling of the array. */
vector<int> shuffle() {
vector<int> t(v);
for(int i=0;i<size - 1;i++){
int r = randomBetween(i, size-1);
swap(t[i], t[r]);
}
return t;
}

inline void swap(int &a, int &b){
int t = a;
a = b;
b = t;
}

int randomBetween(int a, int b){
if(a == b) return a;
if(a > b) return randomBetween(b, a);
return rand() % (b-a+1) + a;
}
};

/**
* 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();
*/
``````