Java 编程题 汇总

抽彩游戏，从n个数中随机选取k个

public class LotteryDrawing {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        System.out.println("How many numbers do you need draw? ");
        int k = in.nextInt();
        System.out.println("What is the highest number you can draw");
        int n = in.nextInt();
        int[] numbers = new int[n];
        for (int i = 0 ; i < numbers.length; i++) {
            numbers[i] = i + 1;
        }
        //draw k number and put them into a second array
        int[] result = new int[k];
        for (int i = 0; i < result.length; i++) {
            int r = (int) (Math.random() * n);
            result[i] = numbers[r];
            numbers[r] = numbers[n - 1];
            n--;
        }
        //print the sorted array
        Arrays.sort(result);
        System.out.println("Bet the following combination. It'll make you rich!");
        for (int r : result) {
            System.out.println(r);
        }
    }
}