Java第八次上机作业

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)

 

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a[] = { 10, 20, 30, 40, 50 };
        for (int i = 0; i < a.length; i++) {
            System.out.println(a[i]);
        }
    }

}

 

2、将一个字符数组的值(neusoft)拷贝到另一个字符数组中。(知识点:数组复制)

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String[] a = { "neusoft" };
        String[] b = new String[a.length];
        System.arraycopy(a, 0, b, 0, a.length);
        for (String string : b) {
            System.out.println(string);
        }
    }

}

 

 

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)

 

import java.util.Arrays;

public class test {

    /**
     * @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);
        }
    }

}

 

public class test {

    /**
     * @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 - 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;
                }
            }
        }
        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)

 

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        double a[][] = { { 1, 2, 3, 4 }, { 5, 6, 7, 8 }, { 9, 10, 11, 12 },
                { 13, 14, 15, 16 }, { 17, 18, 19, 20 } };
        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)

 

public class test {

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

}

 

 

 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 test {

    /**
     * @param args
     */
    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)

 

public class homework3 {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a[] = { 10, 14, 13, 14, 12, 77, 50 };
        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] = 0;
            }
        }
        for (int i : a) {
            System.out.println(i);
        }
    }
}

 

8、给定一维数组{ -1023246-10005},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)

 

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int a[] = { -10, 2, 3, 246, -100, 0, 5 };
        int avg = 0, max = 0, min = 0;
        int sum = 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("平均数" + avg + "最大" + max + "最小" + min);
    }

}

 

 

 9、使用数组存放裴波那契数列的前20项 ,并输出

public class test {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        int[] x = new int[20];
        x[0] = 1;
        x[1] = 1;
        for (int i = 2; i < x.length; i++) {
            x[i] = x[i - 1] + x[i - 2];
        }
        for (int i = 0; i < 8; i++) {
            System.out.print(x[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

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

public class test {
    public static void main(String[] args) {
        Random r = new Random();
        int x[] = new int[10];
        for (int i = 0; i < x.length; i++) {
            x[i] = r.nextInt(101);
        }
        for (int i = 0; i < x.length; i++) {
            System.out.print(x[i] + " ");
        }
        System.out.println("排序后:");
        Arrays.sort(x);
        for (int i = 0; i < x.length; i++) {
            System.out.print(x[i] + " ");
        }
    }
}

 

posted @ 2021-04-27 10:07  热血青年小刘  阅读(88)  评论(0编辑  收藏  举报