DS220702-0707作业

#1.已有数组保存1,3,5,2,4,6

控制台输出：6 4 2 5 3 1 

public class Main {
    public static void main(String[] args) {
        int[] arr = {1,3,5,2,4,6};
        for (int i = arr.length-1; i >=0 ; i--) {
            System.out.print(arr[i]+" ");
        }
    }
}

#2、已有数组保存1,5,9,3,5,7，请颠倒数组元素的存放位置并输出

注意：颠倒后的数组{7,5,3,9,5,1}
控制台输出：7 5 3 9 5 1

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        int[] arr = {1,5,9,3,5,7};
        for (int i = 0; i < arr.length/2; i++) {
            int a = arr[i];
            arr[i] = arr[arr.length-1-i];
            arr[arr.length-1-i] = a;
        }
        System.out.println(Arrays.toString(arr));
    }
}

#3、求出数组{15,35,5,-20,60}中的最大值和最小值

控制台输出：
	最大值：60
	最小值：-20

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {
        int[] arr = {15,35,5,-20,60};
        int max = arr[0],min = arr[0];
        for (int i = 1; i < arr.length; i++) {
            if (arr[i] > max){
                max = arr[i];
            }
            if (min > arr[i]){
                min = arr[i];
            }
        }
        System.out.println("最大值是："+max);
        System.out.println("最小值是："+min);
    }
}

#4、键盘输入10个数，存到数组中，打印奇数位元素的值

注意：如果数组是{10,11,12,13,14,15},则奇数位元素是10，12，14

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        int[] arr = new int[10];
        Scanner sc = new Scanner(System.in);
        for (int i = 0; i < arr.length; i++) {
            arr[i] = sc.nextInt();
            if ((i+1)%2!=0){
                System.out.print(arr[i]+" ");
            }
        }
    }
}

#5、有数组{1,22,0,3,44,0,0,5,66,7,0,0,0,88,9}

要求生成一个不包含0的新数组，并控制台遍历该数组
新数组：{1,22,3,44,5,66,7,88,9}

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

public class Main {
    public static void main(String[] args) {
        int[] arr = {1,22,0,3,44,0,0,5,66,7,0,0,0,88,9};
        List list = new ArrayList();
        for (int i = 0; i < arr.length; i++) {
            if (arr[i]!=0){
                list.add(arr[i]);
            }
        }
        Object[] brr = list.toArray();
        System.out.println(Arrays.toString(brr));
    }
}