一月二十二日星期四

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class FindNumber {
    @SuppressWarnings("resource")
    public static void main(String[] args) {
        List<Integer> arraylist1 = new ArrayList<Integer>();
        List<Integer> arraylist2 = new ArrayList<Integer>();
        List<Integer> replacedindexlist = new ArrayList<Integer>();
        int arraylength = 0;
        int repeatednumber = 0;
        // Scanner sc = new Scanner(System.in);
        // n = sc.nextInt();
        // 输入异常改进
        // 这里一定要将控制状态标志的Scanner对象放入while循环内.否则第一次输入异常后进入死循环!
        boolean flags1 = false;
        while (!flags1) {
            System.out.println("请输入数组元素个数:");
            Scanner sc1 = new Scanner(System.in);
            boolean flagsn = sc1.hasNextInt();
            if (flagsn) {
                arraylength = sc1.nextInt();
                boolean flagsm = false;
                flagsm: while (!flagsm) {
                    System.out.println("请输入重复数字个数:");
                    Scanner sc2 = new Scanner(System.in);
                    flagsm = sc2.hasNextInt();
                    if (flagsm) {
                        repeatednumber = sc2.nextInt();
                        if(repeatednumber<=arraylength){
                            flags1 = true;
                        }else{
                            System.out.println("重复数字个数不得大于数组长度!");
                            break flagsm;
                        }
                    } else {
                        System.out.println("输入整数!");
                    }
                }
            } else {
                System.out.println("输入整数!");
            }
        }
        int arraylengthcount = 0;
        while (arraylengthcount < arraylength) {
            Integer randomnumber = (int) (Math.random() * arraylength + 1);
            if (!arraylist1.contains(randomnumber)) {
                arraylist1.add(randomnumber);
                arraylengthcount++;
            }
        }
        System.out.println("生成的数组:" + Arrays.toString(arraylist1.toArray()));
        int repeatednumbercount = 0;
        while (repeatednumbercount < repeatednumber) {
            // arraylist1.set(replacedindex,repeatednumber);
            // n较小时可能没有重复的数字,改进
            int randomnumber = (int) (Math.random() * arraylength + 1);
            int replacedindex = (int) (Math.random() * arraylength);
            if (!replacedindexlist.contains(replacedindex)) {
                replacedindexlist.add(replacedindex);
                arraylist1.set(replacedindex, randomnumber);
                repeatednumbercount++;
            }
        }
        // System.out.println("数组列表长度:"+arraylist.size());
        for (int i : arraylist1) {
            if (!arraylist2.contains(i)) {
                arraylist2.add(i);
            } else {
                System.out.println("找到你啦哈哈:" + i);
            }
        }
//        System.out.println("数组列表1长度:" + arraylist1.size());
        System.out.println("含有重复元素的数组:" + Arrays.toString(arraylist1.toArray()));
//        System.out.println("数组列表2长度:" + arraylist2.size());
//        System.out.println("数组列表2:" + Arrays.toString(arraylist2.toArray()));
    }
}