Java基础洗牌案例

package com.yongsheng.first;
/***
 * 洗牌案列
 * @author Yongsheng
 * @version 1.0
 * 创建时间:2018年5月19日 下午3:26:56
 */
public class ShuffleCardsDemo {

	public static void main(String[] args) {
	final int N = 52;
	//	 52张牌
     int[] cards = new int[N];
     for (int i = 0; i < cards.length; i++) {
		cards[i] = i;
	}
     //牌的花色数组
     String[] cardColors = {"黑桃","红桃","方块","梅花"};
     //牌的数组
     String[] cardValues = {"A","1","2","3","4","5","6","7","8","9","J",
    		 "Q","K"};
     System.out.println("洗牌前:");
     for (int i = 0; i < cards.length; i++) {
		System.out.printf("%s-%s",cardColors[cards[i]/13],cardValues[cards[i]%13] );
		if(cards[i]%13 == 1)	
		{	
			System.out.println();
		}else{
			System.out.print("\t");
		}
	}
     
     
     //洗牌：随机生成一个随机数字0~51之间的数字numIndex,numIndex和carsds[i]交换
     for (int i = 0; i < cards.length; i++) {
		int newIndex =(int)(Math.random()*N);//0~51之间的元素
		int temp = cards[i];
		cards[i] = cards[newIndex];
		cards[newIndex]= temp;
	}
   System.out.println();
     System.out.println("洗牌后:");
     for (int i = 0; i < cards.length; i++) {
		System.out.printf("%s-%s",cardColors[cards[i]/13],cardValues[cards[i]%13] );
		if((i+1)%13 == 0)	
		{	
			System.out.println();
		}else{
			System.out.print("\t");
		}
	}
	}

}