Input
["Solution", "shuffle", "reset", "shuffle"]
[[[1, 2, 3]], [], [], []]
Output
[null, [3, 1, 2], [1, 2, 3], [1, 3, 2]]
Explanation
Solution solution = new Solution([1, 2, 3]);
solution.shuffle(); // Shuffle the array [1,2,3] and return its result.
// Any permutation of [1,2,3] must be equally likely to be returned.
// Example: return [3, 1, 2]
solution.reset(); // Resets the array back to its original configuration [1,2,3]. Return [1, 2, 3]
solution.shuffle(); // Returns the random shuffling of array [1,2,3]. Example: return [1, 3, 2]
/**
* @param {number[]} nums
*/
class Solution{
constructor(nums){
this.original = [...nums];
this.nums = nums;
}
reset() {
this.nums = [...this.original];
return this.nums;
}
shuffle() {
for(let i = this.nums.length - 1; i > 0; i--){
const random = Math.floor(Math.random() * (i + 1));
[this.nums[i], this.nums[random]] = [this.nums[random], this.nums[i]];
}
return this.nums;
}
};
/**
* @param {number[]} nums
*/
var Solution = function(nums) {
this.nums = [...nums];
this.originalNums = [...nums];
return this;
};
/**
* @return {number[]}
*/
Solution.prototype.reset = function() {
return this.originalNums;
};
/**
* @return {number[]}
*/
Solution.prototype.shuffle = function() {
const { floor, random } = Math;
for (let i = 0; i < this.nums.length; i += 1) {
const randomIndex = floor(random() * this.nums.length);
[this.nums[i], this.nums[randomIndex]] = [this.nums[randomIndex], this.nums[i]]
}
return this.nums
};
/**
* Your Solution object will be instantiated and called as such:
* var obj = new Solution(nums)
* var param_1 = obj.reset()
* var param_2 = obj.shuffle()
*/
var Solution = function(nums) {
this.nums = nums;
this.arr = [...nums];
};
Solution.prototype.reset = function() {
return this.nums;
};
Solution.prototype.shuffle = function() {
const arr = this.arr;
arr.forEach((_, idx) => {
const randomIdx = Math.floor(Math.random() * arr.length);
[arr[randomIdx], arr[idx]] = [arr[idx], arr[randomIdx]];
});
return this.arr;
};
