M面经prepare: Shuffle a deck

设计一个shuffle card

用了java. Random Class

 package Random;
 import java.util.*;

 public class Solution {
     static int cardNum = 10;
     public int[] shuffle(int[] cards) {
         //ArrayList<Integer> res = new ArrayList<Integer>();
         Random rnd = new Random();
         for(int i=0; i<cardNum; i++){
             int rand = rnd.nextInt(cardNum-i)+i;
             int temp = cards[i];
             cards[i] = cards[rand];
             cards[rand] = temp;
         }
         return cards;
     }

     /**
      * @param args
      */
     public static void main(String[] args) {
         // TODO Auto-generated method stub
         Solution sol = new Solution();
         int[] array = new int[cardNum];
         for (int i=0; i<cardNum; i++) array[i] = i;
         int[] res = sol.shuffle(array);
         System.out.println(Arrays.toString(res));
     }

 }