Java练习题1

题目1： 编程实现，现在有如下的一个数组：

int oldArr[] = {1,3,4,5,0,0,6,6,0,5,4,7,6,7,0,5};

要求将以上数组中值为0的项去掉，将不为0的值存入一个新的数组，生成的新数组为。

int newArr[]={1,3,4,5,6,6,5,4,7,6,7,5};

public class Exer {

    public static int[] getNewArr(int[] arr){
        int count=0;
        
        for(int i : arr) {
            if(i != 0) {
                count++;
            }
        }
        
        int j = 0;
        int[] newArr=new int[count];
        for(int i =0;i<arr.length;i++) {
            if(arr[i] != 0) {
                newArr[j]=arr[i];
                j++;
            }
        }
        
        return  newArr;
    }
    
    public static void main(String args[]) {
        int oldArr[] = {1,3,4,5,0,0,6,6,0,5,4,7,6,7,0,5};
        
        
        int[] newArr = getNewArr(oldArr);
        System.out.print("int newArr[]={");
        for(int i=0;i<newArr.length;i++) {
            if(i==newArr.length-1) {
                System.out.print(newArr[i] + "};");                
            }else {
                System.out.print(newArr[i] + ",");                
            }
        }
    }
}

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题目2：编程实现，要求程序输出某两个整数之间的随机整数。

import java.util.Random;
import java.util.Scanner;

public class exer1 {

    public static void getRandomNumBetweenXAndY(int x,int y) {
        Random rand = new Random();
        //获取两个数之间的绝对值
        int abs = Math.abs(x-y);
        
        if(abs <= 1) {
            System.out.println(x + "和" + y + "之间已经没有随机整数了");
        }else {
            //获取两个数之间的随机数，选择最小的数作为底数，然后加上两个值之间的绝对值的随机整数
            int randomNum =  x > y ? rand.nextInt(abs) + y : rand.nextInt(abs) + x;
            System.out.println(x + "和" + y + "之间的随机数是：" + randomNum);
        }
    }
    public static void main(String args[]) {
        //从控制台获取x和y的值
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入x的值");
        int x = scanner.nextInt();
        System.out.println("请输入y的值");
        int y = scanner.nextInt();
        //调用方法获取x和y之间的随机整数
        getRandomNumBetweenXAndY(x,y);
    }
}