shuffle-an-array.rs

#![allow(dead_code, unused, unused_variables)]

fn main() {}

/**
 * Your Solution object will be instantiated and called as such:
 * let obj = Solution::new(nums);
 * let ret_1: Vec<i32> = obj.reset();
 * let ret_2: Vec<i32> = obj.shuffle();
 */
struct Solution {
    nums: Vec<i32>,
}

/**
 * `&self` means the method takes an immutable reference.
 * If you need a mutable reference, change it to `&mut self` instead.
 */
impl Solution {
    fn new(nums: Vec<i32>) -> Self {
        Self { nums }
    }

    /** Resets the array to its original configuration and return it. */
    fn reset(&self) -> Vec<i32> {
        self.nums.clone()
    }

    /** Returns a random shuffling of the array. */
    fn shuffle(&self) -> Vec<i32> {
        use rand::Rng;

        let mut rng = rand::thread_rng();
        let mut v = self.nums.clone();
        for i in 0..self.nums.len() {
            v.swap(rng.gen_range(0..self.nums.len()), i);
        }
        v
    }
}