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java第八次作业

1编写一个简单程序,要求数组长度为5,分别赋值1020304050,在控制台输出该数组的值。(知识点:数组定义和创建、一维数组初始化)[必做题]?

 

package com;

public class Test1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int [] a={1,2,3,4,5};
        for (int i = 0; i < a.length; i++) {
            System.out.println(a[i]);
        }
    }

}

 

 

 

 

 

2将一个字符数组的值(neusofteducation)拷贝到另一个字符数组中。(知识点:数组复制) [必做题]?

 

package com;

public class Test2 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        char []neusofteducation={'m','i','l','k','h','f'};
        char []y=new char[neusofteducation.length];
        System.arraycopy(neusofteducation, 0, y, 0, neusofteducation.length);
        for (char i : y) {
            System.out.println(i);
        }

    }

}

 

 

 

 

 

3给定一个有9个整数(1,6,2,3,9,4,5,7,8)的数组,先排序,然后输出排序后的数组的值。(知识点:Arrays.sort排序、冒泡排序)

 

package com;

import java.util.Arrays;


public class Test3 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int []a={1,6,2,3,9,4,5,7,8};
        Arrays.sort(a);
        for (int i : a) {
            System.out.println(i);
        }

    }

}

 

 

 

 

4输出一个double型二维数组(长度分别为54,值自己设定)的值。(知识点:数组定义和创建、多维数组初始化、数组遍历)

 

package com;

public class Test4 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        double a[][]=new double [5][4];
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a[i].length; j++) {
                a[i][j]=i+j;
            }
        }
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a[i].length; j++) {
                System.out.print(a[i][j]+"  ");
            }
            System.out.println();
        }

    }

}

 

 

 

 5

在一个有8个整数(18257361328963)的数组中找出其中最大的数及其下标。(知识点:数组遍历、数组元素访问) [必做题]?

 

package com;

public class Test5 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int [] a={18,25,7,36,13,2,89,63};
        int max=a[0];
        for (int i = 0; i < a.length; i++) {
            if (max<a[i]) {
                max=a[i];
            }
        }
        System.out.println("最大值为"+max);
        int b=0;
        for (int i = 0; i < a.length; i++) {
            if (a[i]==max) {
                System.out.println("下标是"+b);
            }
            b++;
        }

    }

}

 

 

 

 6将一个数组中的元素逆序存放(知识点:数组遍历、数组元素访问)

import java.util.Scanner;

public class Test7 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        int []a=new int[5];
        for (int i = 0; i < a.length; i++) {
            a[i]=input.nextInt();
        }
        int temp;
        for (int i = 0; i < a.length/2; i++) {
            temp=a[i];
            a[i]=a[a.length-i-1];
            a[a.length-i-1]=temp;    
        }
        for (int i = 0; i < a.length; i++) {
            System.out.print(a[i]+"  ");
            
        }

    }

}

 

7. 将一个数组中的重复元素保留一个其他的清零。(知识点:数组遍历、数组元素访问)

package com;

import java.util.Scanner;

public class Test7 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int []a= {1,1,23,2,4,8,8};
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a.length; j++) {
                if(a[i]==a[j]&&i!=j) {
                    a[j]=1;
                }
            }
        }
        for (int i : a) {
            System.out.println(i);
        }

    }

}

 

 8、给定一维数组{ -10,2,3,246,-100,0,5},计算出数组中的平均值、最大值、最小值。(知识点:数组遍历、数组元素访问)

package com;

import java.util.Scanner;

public class Test7 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
         int []a={ -10,2,3,246,-100,0,5};
            int max=a[0];
            int min=a[0];
            int sum=0;
            double ave=sum/7;
            for (int i = 0; i < a.length; i++) {
                if(a[i]>max){
                    max=a[i];
                }
                if(a[i]<min){
                    min=a[i];
                }
                sum+=a[i];
                ave=sum/7.0;
            }
            System.out.println("最大值为="+max+"最小值为="+min+"平均值="+ave);

    }

}

 

 

 9、使用数组存放裴波那契数列的前20项 ,并输出 1 1 2 3 5 8 13 21

package com;

import java.util.Arrays;
import java.util.Scanner;

public class Test7 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int []a=new int[20];
        a[0]=1;
        a[1]=1;
        for (int i = 2; i < a.length; i++) {
            a[i]=a[i-1]+a[i-2];
        }
        System.out.println(Arrays.toString(a));

    }

}

 

 10、生成一个长度为10的随机整数数组(每个数都是0-100之间),输出,排序后,再输出

package com;

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

public class Test7 {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
         Random random = new Random(10);
            int b[] = new int[10];
            for (int i = 0; i < b.length; i++) {
                b[i] = random.nextInt(200);
                System.out.print(" "+b[i]);
                
            }
            System.out.println();
            for (int i = 0; i < b.length - 1; i++) {
                for (int j = 0; j < b.length - 1 - i; j++) {
                    if (b[j] > b[j + 1]) {
                        int temp = b[j];
                        b[j] = b[j + 1];
                        b[j + 1] = temp;
                    }
                }
            }
            System.out.println();
            for (int i = 0; i < b.length; i++) {
                System.out.print(" " + b[i]);
            }
    }
}

 

 

 

posted on 2021-04-26 19:50  HumbleSwag  阅读(52)  评论(0编辑  收藏  举报