【经典练习题】

1、模拟双色球生成案例
需求：体彩中有一项是双色球，要求在1-33号共33个红色球里选出6个，1-16号共16个蓝色球中选出一个作为中奖号码，请实现这个需求

package PracticeSomeCode;

import java.util.Arrays;
import java.util.Random;

public class ColorBall {
	public static void main(String[] args) {
		int[] red = ballBox(33);
		int[] blue = ballBox(15);
		System.out.println(Arrays.toString(red));
		System.out.println(Arrays.toString(blue));
		
		int[] redResult = select(red,6);
		int[] blueResult = select(blue,1);
		System.out.println("红球："+Arrays.toString(redResult));
		System.out.println("篮球："+Arrays.toString(blueResult));
	}
	public static int[] ballBox(int n){
		int[] box = new int[n];
		for(int i = 0; i < n ; i++ ){
			box[i] = i+1;
		}
		return box;
	}
	public static int[] select(int[] ballBox, int n){
		for(int i = 0; i < n ; i++){
			int j = new Random().nextInt(ballBox.length-i);
			int temp = ballBox[i];
			ballBox[i] = ballBox[j];
			ballBox[j] = temp;
		}
		int[] result = Arrays.copyOf(ballBox,n);
		return result;
	}
}