java第8次作业

1、编写一个简单程序,要求数组长度为5,分别赋值10,20,30,40,50,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 jj;

import java.util.Scanner;

public class a {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int [] a=new int[5];
        Scanner input=new Scanner(System.in);
        for (int i = 0; i < a.length; i++) {
            a[i]=input.nextInt();
            
        }
        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 jj;

public class b {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        char[] a={'n','e','u','s','o','f','t','e','d','u','c','a','t','i','o','n'};
        char[] b=new char [a.length];
        System.arraycopy(a,0,b,0,a.length);
        for (int i = 0; i < b.length; i++) {
            System.out.print(b[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 jj;

public class c {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] a={1,6,2,3,9,4,5,7,8};
        for (int i = 0; i < a.length; i++) {
            for (int j = 0; j < a.length-1-i; j++) {
                if (a[j]>a[j+1]) {
                    int temp=a[j];
                    a[j]=a[j+1];
                    a[j+1]=temp;
                    
                }
                
            }
            
        }
        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 jj;

import java.util.Scanner;

public class d {

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

public class e {

    /**
     * @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],id=0;
        for (int i = 1; i < a.length; i++) {
            if (a[i]>max) {
                max=a[i];
                id=i;
                
            }
            
        }
        System.out.println("最大"+max+"下标"+id);
    }

}

 

 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) [选作题]

package cc;

import java.util.Scanner;

public class test1 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
         Scanner input=new Scanner(System.in);
         System.out.println("请输入");
            int a[]=new int[5];
            for (int i = a.length; i >0; i--) {
                a[i-1]=input.nextInt();
            }
            System.out.println("倒序输出");
            for (int i = 0; i < a.length; i++) {
                System.out.println(a[i]);
            }
     
        }
     
    }

7. 将一个数组中的重复元素保留一个其他的清零。

package cc;

import java.util.Scanner;

public class test2 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Scanner input=new Scanner(System.in);
        int a[]=new int[5];
        System.out.println("请输入");
        for (int i = 0; i < a.length; i++) {
            a[i]=input.nextInt();
        }
        for (int i = 0; i < a.length-1; i++) {
            for (int j = i+1; j < a.length; j++) {
                if(a[i]==a[j]){
                    a[j]=0;
                }
            }
        }
        for (int i = 0; i < a.length; i++) {
            System.out.println(a[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。

package cc;

import java.util.Scanner;


public class test3 {

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

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 cc;

import java.util.Scanner;

public class test4 {

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

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 cc;

import java.util.Random;


public class test5 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
         Random random = new Random(10);
            int a[] = new int[10];
            for (int i = 0; i < a.length; i++) {
                a[i] = random.nextInt(100);
                System.out.println(a[i]);
                
            }
            System.out.println();
            for (int i = 0; i < a.length - 1; i++) {
                for (int j = 0; j < a.length - 1 - i; j++) {
                    if (a[j] > a[j + 1]) {
                        int temp = a[j];
                        a[j] = a[j + 1];
                        a[j + 1] = temp;
                    }
                }
            }
            System.out.print("排序后结果为");
            System.out.println();
            for (int i = 0; i < a.length; i++) {
                System.out.println( a[i]);
            }
        }
    }

 

 

 

posted @ 2021-04-26 21:42  ♡十梦九你♡  阅读(44)  评论(0编辑  收藏  举报