定义一个ClassName接口，接口中只有一个抽象方法getClassName()；设计一个类Company，该类实现接口ClassName中的方法getClassName()，功能是获取该类的类名称；编写应用程序使用Company类
输出格式:
输出类名称。
输出样例:
Company
源代码：
1 interface ClassName { 2 public abstract void getClassName(); 3 } 4 5 class Company implements ClassName { 6 @Override 7 public void getClassName() { 8 9 System.out.print(Company.class.getSimpleName()); 10 } 11 } 12 13 public class Main { 14 public static void main(String args[]) { 15 Company a = new Company(); 16 a.getClassName(); 17 } 18 }
2 给定两个点的坐标，求解两个点的距离。 (20分)
给定两个点的坐标，求解两个点的距离。
输入格式:
给定四个浮点数，作为线段的两个点。
输出格式:
输出该线段的距离。
输入样例:
0 0 1.0 1.0
输出样例:
The distance is 1.41
源代码：
1 import java.util.Scanner; 2 3 public class Main{ 4 5 public static void main(String[] args) { 6 Scanner in = new Scanner(System.in); 7 double a1 = in.nextDouble(); 8 double a2 = in.nextDouble(); 9 double a3 = in.nextDouble(); 10 double a4 = in.nextDouble(); 11 double s = Math.sqrt(Math.pow((a3-a1), 2)+Math.pow((a3-a1),2)); 12 System.out.println(String.format("The distance is "+"%.2f", s)); 13 14 } 15 16 }
3 找出最大的对象 (10分)
（找出最大的对象）编写一个方法，返回对象数组中最大的对象。方法签名如下：
public static Object max(Comparable[] a)
所有对象都是Comparable接口的实例。对象在数组中的顺序是由compareTo方法决定的。
编写测试程序，从键盘输入5个字符串和5个整数，创建一个由5个字符串构成的数组、一个由5个整数构成的数组。找出数组中最大的字符串、整数并输出。
输入格式:
输入 Xi‘an （输入5个字符串，每行一个） Beijing ShangHai GuangZhou ShenZhen 8 9 12 7 6 （输入5个整数，以空格分隔）
输出格式:
输出 Max string is Xi‘an （输出最大的字符串）
Max integer is 12 （输出最大的整数）
输入样例:
France
Japan
German
China
India
6 34 89 168 53
输出样例:
Max string is Japan
Max integer is 168
源代码：
1 import java.util.Arrays; 2 import java.util.Scanner; 3 public class Main { 4 5 public static void main(String[] args) { 6 @SuppressWarnings("resource") 7 Scanner sc = new Scanner(System.in); 8 String [] list1 = new String[5]; 9 int [] list2 = new int[5]; 10 for(int i=0;i<5;i++){ 11 String str1 = sc.next(); 12 list1[i]=str1; 13 } 14 for(int i=0;i<5;i++){ 15 int str2 = sc.nextInt(); 16 list2[i]=str2; 17 } 18 19 20 Arrays.sort(list1); 21 Arrays.sort(list2); 22 System.out.println("Max string is "+list1[4]); 23 System.out.println("Max integer is "+list2[4]); 24 } 25 }
4 字符串替换 (20分)
将文本文件中指定的字符串替换成新字符串。 由于目前的OJ系统暂时不能支持用户读入文件，我们编写程序从键盘输入文件中的内容，当输入的一行为end时，表示结束。end后面有两个字符串，要求用第二个字符串替换文本中所有的第一个字符串。
输入格式:
Xi’an Institute of Posts and Telecommunications is co-designed and implemented by the People’s Government of Shaanxi Province and the Ministry of Industry and Information Technology. The Institute is located in Xi’an, a historic city in Northwest China, famous for its magnificent ancient culture. end （表示结束） Institute （第一个字符串，要求用第二个字符串替换） University （第二个字符串）
输出格式:
Xi’an University of Posts and Telecommunications is co-designed and implemented by the People’s Government of Shaanxi Province and the Ministry of Industry and Information Technology.The University is located in Xi’an, a historic city in Northwest China, famous for its magnificent ancient culture.
输入样例:
Xi’an Institute of Posts and Telecommunications is co-designed and implemented by the People’s Government of Shaanxi Province and the Ministry of Industry and Information Technology. The Institute is located in Xi’an, a historic city in Northwest China, famous for its magnificent ancient culture. end Institute University
输出样例:
Xi’an University of Posts and Telecommunications is co-designed and implemented by the People’s Government of Shaanxi Province and the Ministry of Industry and Information Technology.The University is located in Xi’an, a historic city in Northwest China, famous for its magnificent ancient culture.
源代码：
1 import java.io.*; 2 import java.util.*; 3 4 public class Main{ 5 public static void main(String[] args) throws IOException { 6 String x = null; 7 Scanner in = new Scanner(System.in); 8 String str = ""; 9 x = in.nextLine(); 10 while (!x.equals("end")) { 11 str += x; 12 x = in.nextLine(); 13 } 14 String a = in.nextLine(); 15 String b = in.nextLine(); 16 in.close(); 17 String str1 = str.replace(a, b); 18 System.out.println(str1); 19 20 } 21 }
5 求阶乘factorial (20分)
编程从键盘输入一个整数，计算出阶乘并输出。
输入格式:
输入 39
输出格式:
输出：20397882081197443358640281739902897356800000000
输入样例:
58
输出样例:
2350561331282878571829474910515074683828862318181142924420699914240000000000000
源代码：
1 import java.math.BigInteger; 2 import java.util.Scanner; 3 4 public class Main { 5 public static void main(String args[]) { 6 BigInteger sum = new BigInteger("1"); 7 Scanner in = new Scanner(System.in); 8 int n = in.nextInt(); 9 for(int i = 1; i<= n;i++){ 10 String temp1 = Integer.toString(i); 11 BigInteger temp2 = new BigInteger(temp1); 12 sum = sum.multiply(temp2); 13 } 14 System.out.println(sum); 15 16 } 17 }
