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201771010101 白玛次仁《面向对象程序设计(Java)》第十一周学习总结

实验十一   集合

实验时间 2018-11-8

1、实验目的与要求

(1) 掌握Vetor、Stack、Hashtable三个类的用途及常用API;

(2) 了解java集合框架体系组成;

(3) 掌握ArrayList、LinkList两个类的用途及常用API。

(4) 了解HashSet类、TreeSet类的用途及常用API。

(5)了解HashMap、TreeMap两个类的用途及常用API;

(6) 结对编程(Pair programming)练习,体验程序开发中的两人合作。

2、实验内容和步骤

实验1: 导入第9章示例程序,测试程序并进行代码注释。

测试程序1:

l 使用JDK命令运行编辑、运行以下三个示例程序,结合运行结果理解程序;

l 掌握Vetor、Stack、Hashtable三个类的用途及常用API。 

//示例程序1

import java.util.Vector;

 

class Cat {

private int catNumber;

 

Cat(int i) {

catNumber = i;

}

 

void print() {

System.out.println("Cat #" + catNumber);

}

}

 

class Dog {

private int dogNumber;

 

Dog(int i) {

dogNumber = i;

}

 

void print() {

System.out.println("Dog #" + dogNumber);

}

}

 

public class CatsAndDogs {

public static void main(String[] args) {

Vector cats = new Vector();

for (int i = 0; i < 7; i++)

cats.addElement(new Cat(i));

cats.addElement(new Dog(7));

for (int i = 0; i < cats.size(); i++)

((Cat) cats.elementAt(i)).print();

}

}

//示例程序2

import java.util.*;

 

public class Stacks {

static String[] months = { "1", "2", "3", "4" };

 

public static void main(String[] args) {

Stack stk = new Stack();

for (int i = 0; i < months.length; i++)

stk.push(months[i]);

System.out.println(stk);

System.out.println("element 2=" + stk.elementAt(2));

while (!stk.empty())

System.out.println(stk.pop());

}

}

//示例程序3

import java.util.*;

 

class Counter {

int i = 1;

 

public String toString() {

return Integer.toString(i);

}

}

 

public class Statistics {

public static void main(String[] args) {

Hashtable ht = new Hashtable();

for (int i = 0; i < 10000; i++) {

Integer r = new Integer((int) (Math.random() * 20));

if (ht.containsKey(r))

((Counter) ht.get(r)).i++;

else

ht.put(r, new Counter());

}

System.out.println(ht);

}

}

示例程序1

package demo; import java.util.Vector; class Cat { private int catNumber; Cat(int i) { catNumber = i; } void print() { System.out.println("Cat #" + catNumber); } } class Dog { private int dogNumber; Dog(int i) { dogNumber = i; } void print() { System.out.println("Dog #" + dogNumber); } } public class CatsAndDogs { public static void main(String[] args) { Vector cats = new Vector(); for (int i = 0; i < 7; i++) cats.addElement(new Cat(i)); cats.addElement(new Dog(7)); for (int i = 0; i < 7; i++) ((Cat) cats.elementAt(i)).print(); ((Dog) cats.elementAt(7)).print(); } }

  

 

import java.util.*;

 

public class Stacks {

static String[] months = { "1", "2", "3", "4" };

 

public static void main(String[] args) {

Stack stk = new Stack();

for (int i = 0; i < months.length; i++)

stk.push(months[i]);

System.out.println(stk);

System.out.println("element 2=" + stk.elementAt(2));

while (!stk.empty())

System.out.println(stk.pop());

}

}

 

 

package demo;

import java.util.*;

class Counter {
    int i = 1;
    //default:

    public String toString() {
        return Integer.toString(i);
    }
}

public class Statistics {
    public static void main(String[] args) {
        Hashtable ht = new Hashtable();
        for (int i = 0; i < 10000; i++) {
            Integer r = new Integer((int) (Math.random() * 20));
            //用Math.random()
            if (ht.containsKey(r))
                ((Counter) ht.get(r)).i++;
            else
                ht.put(r, new Counter());
            //输出r中数据的键值对出现的次数
        }
        System.out.println(ht);
    }
}

 

 

 

 测试程序2

 

import java.util.*;

 

public class ArrayListDemo {

public static void main(String[] argv) {

ArrayList al = new ArrayList();

// Add lots of elements to the ArrayList...

al.add(new Integer(11));

al.add(new Integer(12));

al.add(new Integer(13));

al.add(new String("hello"));

// First print them out using a for loop.

System.out.println("Retrieving by index:");

for (int i = 0; i < al.size(); i++) {

System.out.println("Element " + i + " = " + al.get(i));

}

}

}

import java.util.*;

public class LinkedListDemo {

    public static void main(String[] argv) {

        LinkedList l = new LinkedList();

        l.add(new Object());

        l.add("Hello");

        l.add("zhangsan");

        ListIterator li = l.listIterator(0);

        while (li.hasNext())

            System.out.println(li.next());

        if (l.indexOf("Hello") < 0)   

            System.err.println("Lookup does not work");

        else

            System.err.println("Lookup works");

   }

}

import java.util.*;

public class ArrayListDemo//ArrayList使用了数组的实现
{
    public static void main(String[] argv) {
        ArrayList al = new ArrayList();
        //在ArrayList中添加大量元素
        al.add(new Integer(11));
        al.add(new Integer(12));
        al.add(new Integer(13));
        al.add(new String("hello"));//下标从0开始,添加4个元素
        // First print them out using a for loop.
        System.out.println("Retrieving by index:");
        for (int i = 0; i < al.size(); i++) {
            System.out.println("Element " + i + " = " + al.get(i));
        }
    }
}

 

 

 

 

l 在Elipse环境下编辑运行调试教材360页程序9-1,结合程序运行结果理解程序;

l 掌握ArrayList、LinkList两个类的用途及常用API。

Arraylist:

 

 

package linkedList;

import java.util.*;

/**
 * This program demonstrates operations on linked lists.
 * @version 1.11 2012-01-26
 * @author Cay Horstmann
 */
public class LinkedListTest
{
   public static void main(String[] args)
   {
      List<String> a = new LinkedList<>();
      a.add("Amy");
      a.add("Carl");
      a.add("Erica");

      List<String> b = new LinkedList<>();
      b.add("Bob");
      b.add("Doug");
      b.add("Frances");
      b.add("Gloria");

      // merge the words from b into a

      ListIterator<String> aIter = a.listIterator();
      Iterator<String> bIter = b.iterator();

      while (bIter.hasNext())
      {
         if (aIter.hasNext()) aIter.next();
         aIter.add(bIter.next());
      }

      System.out.println(a);

      // remove every second word from b

      bIter = b.iterator();
      while (bIter.hasNext())
      {
         bIter.next(); // skip one element
         if (bIter.hasNext())
         {
            bIter.next(); // skip next element
            bIter.remove(); // remove that element
         }
      }

      System.out.println(b);

      // bulk operation: remove all words in b from a

      a.removeAll(b);

      System.out.println(a);
   }
}

 

 

测试程序3:

l 运行SetDemo程序,结合运行结果理解程序;

import java.util.*;

public class SetDemo {

    public static void main(String[] argv) {

        HashSet h = new HashSet(); //也可以 Set h=new HashSet()

        h.add("One");

        h.add("Two");

        h.add("One"); // DUPLICATE

        h.add("Three");

        Iterator it = h.iterator();

        while (it.hasNext()) {

             System.out.println(it.next());

        }

    }

}

 

 

l 在Elipse环境下调试教材365页程序9-2,结合运行结果理解程序;了解HashSet类的用途及常用API。

 

package set;

 

import java.util.*;

/**
 * This program uses a set to print all unique words in System.in.
 * @version 1.12 2015-06-21
 * @author Cay Horstmann
 */
public class SetTest
{
   public static void main(String[] args)
   {
      Set<String> words = new HashSet<>(); // HashSet implements Set
      long totalTime = 0;

      try (Scanner in = new Scanner(System.in))
      {
         while (in.hasNext())
         {
            String word = in.next();
            long callTime = System.currentTimeMillis();
            words.add(word);
            callTime = System.currentTimeMillis() - callTime;
            totalTime += callTime;
         }
      }

      Iterator<String> iter = words.iterator();
      for (int i = 1; i <= 20 && iter.hasNext(); i++)
         System.out.println(iter.next());
      System.out.println(". . .");
      System.out.println(words.size() + " distinct words. " + totalTime + " milliseconds.");
   }
}

 

 

l 在Elipse环境下调试教材367页-368程序9-3、9-4,结合程序运行结果理解程序;了解TreeSet类的用途及常用API。

package treeSet;

import java.util.*;

/**
 * An item with a description and a part number.
 */
public class Item implements Comparable<Item>
{
   private String description;
   private int partNumber;

   /**
    * Constructs an item.
    * 
    * @param aDescription
    *           the item's description
    * @param aPartNumber
    *           the item's part number
    */
   public Item(String aDescription, int aPartNumber)
   {
      description = aDescription;
      partNumber = aPartNumber;
   }

   /**
    * Gets the description of this item.
    * 
    * @return the description
    */
   public String getDescription()
   {
      return description;
   }

   public String toString()
   {
      return "[description=" + description + ", partNumber=" + partNumber + "]";
   }

   public boolean equals(Object otherObject)
   {
      if (this == otherObject) return true;
      if (otherObject == null) return false;
      if (getClass() != otherObject.getClass()) return false;
      Item other = (Item) otherObject;
      return Objects.equals(description, other.description) && partNumber == other.partNumber;
   }

   public int hashCode()
   {
      return Objects.hash(description, partNumber);
   }

   public int compareTo(Item other)
   {
      int diff = Integer.compare(partNumber, other.partNumber);
      return diff != 0 ? diff : description.compareTo(other.description);
   }
}
package treeSet;

import java.util.*;

/**
 * This program sorts a set of item by comparing their descriptions.
 * @version 1.12 2015-06-21
 * @author Cay Horstmann
 */
public class TreeSetTest
{
   public static void main(String[] args)
   {
      SortedSet<Item> parts = new TreeSet<>();
      parts.add(new Item("Toaster", 1234));
      parts.add(new Item("Widget", 4562));
      parts.add(new Item("Modem", 9912));
      System.out.println(parts);

      NavigableSet<Item> sortByDescription = new TreeSet<>(
            Comparator.comparing(Item::getDescription));

      sortByDescription.addAll(parts);
      System.out.println(sortByDescription);
   }
}

 

测试程序4:

l 使用JDK命令运行HashMapDemo程序,结合程序运行结果理解程序;

import java.util.*;

public class HashMapDemo {

   public static void main(String[] argv) {

      HashMap h = new HashMap();

      // The hash maps from company name to address.

      h.put("Adobe", "Mountain View, CA");

      h.put("IBM", "White Plains, NY");

      h.put("Sun", "Mountain View, CA");

      String queryString = "Adobe";

      String resultString = (String)h.get(queryString);

      System.out.println("They are located in: " +  resultString);

  }

}

 

 

 

 

l 在Elipse环境下调试教材373页程序9-6,结合程序运行结果理解程序;

l 了解HashMap、TreeMap两个类的用途及常用API。

package map;

import java.util.*;

/**
 * This program demonstrates the use of a map with key type String and value type Employee.
 * @version 1.12 2015-06-21
 * @author Cay Horstmann
 */
public class MapTest
{
   public static void main(String[] args)
   {
      Map<String, Employee> staff = new HashMap<>();
      staff.put("144-25-5464", new Employee("Amy Lee"));
      staff.put("567-24-2546", new Employee("Harry Hacker"));
      staff.put("157-62-7935", new Employee("Gary Cooper"));
      staff.put("456-62-5527", new Employee("Francesca Cruz"));

      // print all entries

      System.out.println(staff);

      // remove an entry

      staff.remove("567-24-2546");

      // replace an entry

      staff.put("456-62-5527", new Employee("Francesca Miller"));

      // look up a value

      System.out.println(staff.get("157-62-7935"));

      // iterate through all entries

      staff.forEach((k, v) -> 
         System.out.println("key=" + k + ", value=" + v));
   }
}

 

package map;

import java.util.*;

/**
 * This program demonstrates the use of a map with key type String and value type Employee.
 * @version 1.12 2015-06-21
 * @author Cay Horstmann
 */
public class MapTest
{
   public static void main(String[] args)
   {
      Map<String, Employee> staff = new HashMap<>();
      staff.put("144-25-5464", new Employee("Amy Lee"));
      staff.put("567-24-2546", new Employee("Harry Hacker"));
      staff.put("157-62-7935", new Employee("Gary Cooper"));
      staff.put("456-62-5527", new Employee("Francesca Cruz"));

      // print all entries

      System.out.println(staff);

      // remove an entry

      staff.remove("567-24-2546");

      // replace an entry

      staff.put("456-62-5527", new Employee("Francesca Miller"));

      // look up a value

      System.out.println(staff.get("157-62-7935"));

      // iterate through all entries

      staff.forEach((k, v) -> 
         System.out.println("key=" + k + ", value=" + v));
   }
}

 

 

 

实验2:结对编程练习:

l 关于结对编程:以下图片是一个结对编程场景:两位学习伙伴坐在一起,面对着同一台显示器,使用着同一键盘,同一个鼠标,他们一起思考问题,一起分析问题,一起编写程序。

 

l 关于结对编程的阐述可参见以下链接:

 

http://www.cnblogs.com/xinz/archive/2011/08/07/2130332.html

http://en.wikipedia.org/wiki/Pair_programming

l 对于结对编程中代码设计规范的要求参考:

http://www.cnblogs.com/xinz/archive/2011/11/20/2255971.html

 

以下实验,就让我们来体验一下结对编程的魅力。

l 确定本次实验结对编程合作伙伴;

l 各自运行合作伙伴实验九编程练习1,结合使用体验对所运行程序提出完善建议;

穷吉

import java.io;
  2 import java.io.File;
  3 import java.io.FileInputStream;
  4 import java.io.FileNotFoundException;
  5 import java.io.IOException;
  6 import java.io.InputStreamReader;
  7 import java.util.ArrayList;
  8 import java.util.Arrays;
  9 import java.util.Collections;
 10 import java.util.Scanner;
 11 
 12 public class  Test{
 13     private static ArrayList<Student> studentlist;
 14     public static void main(String[] args) {
 15         studentlist = new ArrayList<>();
 16         Scanner scanner = new Scanner(System.in);
 17         File file = new File("C:\\下载\\身份证号.txt");
 18         try {
 19             FileInputStream fis = new FileInputStream(file);
 20             BufferedReader in = new BufferedReader(new InputStreamReader(fis));
 21             String temp = null;
 22             while ((temp = in.readLine()) != null) {
 23                 
 24                 Scanner linescanner = new Scanner(temp);
 25                 
 26                 linescanner.useDelimiter(" ");    
 27                 String name = linescanner.next();
 28                 String number = linescanner.next();
 29                 String sex = linescanner.next();
 30                 String age = linescanner.next();
 31                 String province =linescanner.nextLine();
 32                 Student student = new Student();
 33                 student.setName(name);
 34                 student.setnumber(number);
 35                 student.setsex(sex);
 36                 int a = Integer.parseInt(age);
 37                 student.setage(a);
 38                 student.setprovince(province);
 39                 studentlist.add(student);
 40 
 41             }
 42         } catch (FileNotFoundException e) {
 43             System.out.println("学生信息文件找不到");
 44             e.printStackTrace();
 45         } catch (IOException e) {
 46             System.out.println("学生信息文件读取错误");
 47             e.printStackTrace();
 48         }
 49         boolean isTrue = true;
 50         while (isTrue) {
 51             System.out.println("选择你的操作,输入正确格式的选项");
 52             System.out.println("1.按姓名字典序输出人员信息");
 53             System.out.println("2.输出年龄最大和年龄最小的人");
 54             System.out.println("3.查找老乡");
 55             System.out.println("4.查找年龄相近的人");
 56             System.out.println("5.退出");
 57             String m = scanner.next();
 58             switch (m) {
 59             case "1":
 60                 Collections.sort(studentlist);              
 61                 System.out.println(studentlist.toString());
 62                 break;
 63             case "2":
 64                  int max=0,min=100;
 65                  int j,k1 = 0,k2=0;
 66                  for(int i=1;i<studentlist.size();i++)
 67                  {
 68                      j=studentlist.get(i).getage();
 69                  if(j>max)
 70                  {
 71                      max=j; 
 72                      k1=i;
 73                  }
 74                  if(j<min)
 75                  {
 76                    min=j; 
 77                    k2=i;
 78                  }
 79                  
 80                  }  
 81                  System.out.println("年龄最大:"+studentlist.get(k1));
 82                  System.out.println("年龄最小:"+studentlist.get(k2));
 83                 break;
 84             case "3":
 85                  System.out.println("输入省份");
 86                  String find = scanner.next();        
 87                  String place=find.substring(0,3);
 88                  for (int i = 0; i <studentlist.size(); i++) 
 89                  {
 90                      if(studentlist.get(i).getprovince().substring(1,4).equals(place)) 
 91                          System.out.println("老乡"+studentlist.get(i));
 92                  }             
 93                  break;
 94                  
 95             case "4":
 96                 System.out.println("年龄:");
 97                 int yourage = scanner.nextInt();
 98                 int near=agenear(yourage);
 99                 int value=yourage-studentlist.get(near).getage();
100                 System.out.println(""+studentlist.get(near));
101                 break;
102             case "5":
103                 isTrue = false;
104                 System.out.println("退出程序!");
105                 break;
106                 default:
107                 System.out.println("输入有误");
108 
109             }
110         }
111     }
112         public static int agenear(int age) {      
113         int j=0,min=53,value=0,k=0;
114          for (int i = 0; i < studentlist.size(); i++)
115          {
116              value=studentlist.get(i).getage()-age;
117              if(value<0) value=-value; 
118              if (value<min) 
119              {
120                 min=value;
121                 k=i;
122              } 
123           }    
124          return k;         
125       }
126 
127 }

 

public class Student implements Comparable<Student> {
 2 
 3     private String name;
 4     private String number ;
 5     private String sex ;
 6     private int age;
 7     private String province;
 8    
 9     public String getName() {
10         return name;
11     }
12     public void setName(String name) {
13         this.name = name;
14     }
15     public String getnumber() {
16         return number;
17     }
18     public void setnumber(String number) {
19         this.number = number;
20     }
21     public String getsex() {
22         return sex ;
23     }
24     public void setsex(String sex ) {
25         this.sex =sex ;
26     }
27     public int getage() {
28 
29         return age;
30         }
31         public void setage(int age) {
32             // int a = Integer.parseInt(age);
33         this.age= age;
34         }
35 
36     public String getprovince() {
37         return province;
38     }
39     public void setprovince(String province) {
40         this.province=province ;
41     }
42 
43     public int compareTo(Student o) {
44        return this.name.compareTo(o.getName());
45     }
46 
47     public String toString() {
48         return  name+"\t"+sex+"\t"+age+"\t"+number+"\t"+province+"\n";
49     }    
50 }

 

l 各自运行合作伙伴实验十编程练习2,结合使用体验对所运行程序提出完善建议;

穷吉

package 运算;

import java.util.Scanner;

public class Demo {
	public static void main(String[] args) {
	// 用户的答案要从键盘输入,因此需要一个键盘输入流
@SuppressWarnings("resource")
	Scanner in = new Scanner(System.in);
	// 定义一个变量用来统计得分
int sum = 0;
	// 通过循环生成10道题
for (int i = 0; i < 10; i++) {

// 随机生成两个10以内的随机数作为被除数和除数
int a = (int) Math.round(Math.random() * 10);
	int b = (int) Math.round(Math.random() * 10);
	System.out.println(a + "/" + b + "=");
	// 定义一个整数用来接收用户输入的答案
int c = in.nextInt();
	// 判断用户输入的答案是否正确,正确给10分,错误不给分
if (c == a / b) {
	sum += 10;
	System.out.println("恭喜答案正确");
	}
else {
	System.out.println("抱歉,答案错误");
	}
	}
	//输出用户的成绩
System.out.println("你的得分为"+sum);
	}
}

package 运算;

public class Yuns {
	public int add(int a,int b)
 {
 return a+b;
 }
 public int reduce(int a,int b)
 {
 if((a-b)>0)
 return a-b;
 else return 0;
 }
 public int multiply(int a,int b)
 {
 return a*b;
 }
 public int devision(int a,int b)
 {
 if(b!=0)
 return a/b;
 else return 0;

 }

 

 

l 采用结对编程方式,与学习伙伴合作完成实验九编程练习1;

 

import java.io;
  2 import java.io.File;
  3 import java.io.FileInputStream;
  4 import java.io.FileNotFoundException;
  5 import java.io.IOException;
  6 import java.io.InputStreamReader;
  7 import java.util.ArrayList;
  8 import java.util.Arrays;
  9 import java.util.Collections;
 10 import java.util.Scanner;
 11 
 12 public class  Test{
 13     private static ArrayList<Student> studentlist;
 14     public static void main(String[] args) {
 15         studentlist = new ArrayList<>();
 16         Scanner scanner = new Scanner(System.in);
 17         File file = new File("C:\\下载\\身份证号.txt");
 18         try {
 19             FileInputStream fis = new FileInputStream(file);
 20             BufferedReader in = new BufferedReader(new InputStreamReader(fis));
 21             String temp = null;
 22             while ((temp = in.readLine()) != null) {
 23                 
 24                 Scanner linescanner = new Scanner(temp);
 25                 
 26                 linescanner.useDelimiter(" ");    
 27                 String name = linescanner.next();
 28                 String number = linescanner.next();
 29                 String sex = linescanner.next();
 30                 String age = linescanner.next();
 31                 String province =linescanner.nextLine();
 32                 Student student = new Student();
 33                 student.setName(name);
 34                 student.setnumber(number);
 35                 student.setsex(sex);
 36                 int a = Integer.parseInt(age);
 37                 student.setage(a);
 38                 student.setprovince(province);
 39                 studentlist.add(student);
 40 
 41             }
 42         } catch (FileNotFoundException e) {
 43             System.out.println("学生信息文件找不到");
 44             e.printStackTrace();
 45         } catch (IOException e) {
 46             System.out.println("学生信息文件读取错误");
 47             e.printStackTrace();
 48         }
 49         boolean isTrue = true;
 50         while (isTrue) {
 51             System.out.println("选择你的操作,输入正确格式的选项");
 52             System.out.println("1.按姓名字典序输出人员信息");
 53             System.out.println("2.输出年龄最大和年龄最小的人");
 54             System.out.println("3.查找老乡");
 55             System.out.println("4.查找年龄相近的人");
 56             System.out.println("5.退出");
 57             String m = scanner.next();
 58             switch (m) {
 59             case "1":
 60                 Collections.sort(studentlist);              
 61                 System.out.println(studentlist.toString());
 62                 break;
 63             case "2":
 64                  int max=0,min=100;
 65                  int j,k1 = 0,k2=0;
 66                  for(int i=1;i<studentlist.size();i++)
 67                  {
 68                      j=studentlist.get(i).getage();
 69                  if(j>max)
 70                  {
 71                      max=j; 
 72                      k1=i;
 73                  }
 74                  if(j<min)
 75                  {
 76                    min=j; 
 77                    k2=i;
 78                  }
 79                  
 80                  }  
 81                  System.out.println("年龄最大:"+studentlist.get(k1));
 82                  System.out.println("年龄最小:"+studentlist.get(k2));
 83                 break;
 84             case "3":
 85                  System.out.println("输入省份");
 86                  String find = scanner.next();        
 87                  String place=find.substring(0,3);
 88                  for (int i = 0; i <studentlist.size(); i++) 
 89                  {
 90                      if(studentlist.get(i).getprovince().substring(1,4).equals(place)) 
 91                          System.out.println("老乡"+studentlist.get(i));
 92                  }             
 93                  break;
 94                  
 95             case "4":
 96                 System.out.println("年龄:");
 97                 int yourage = scanner.nextInt();
 98                 int near=agenear(yourage);
 99                 int value=yourage-studentlist.get(near).getage();
100                 System.out.println(""+studentlist.get(near));
101                 break;
102             case "5":
103                 isTrue = false;
104                 System.out.println("退出程序!");
105                 break;
106                 default:
107                 System.out.println("输入有误");
108 
109             }
110         }
111     }
112         public static int agenear(int age) {      
113         int j=0,min=53,value=0,k=0;
114          for (int i = 0; i < studentlist.size(); i++)
115          {
116              value=studentlist.get(i).getage()-age;
117              if(value<0) value=-value; 
118              if (value<min) 
119              {
120                 min=value;
121                 k=i;
122              } 
123           }    
124          return k;         
125       }
126 
127 }

 

 

public class Student implements Comparable<Student> {
 2 
 3     private String name;
 4     private String number ;
 5     private String sex ;
 6     private int age;
 7     private String province;
 8    
 9     public String getName() {
10         return name;
11     }
12     public void setName(String name) {
13         this.name = name;
14     }
15     public String getnumber() {
16         return number;
17     }
18     public void setnumber(String number) {
19         this.number = number;
20     }
21     public String getsex() {
22         return sex ;
23     }
24     public void setsex(String sex ) {
25         this.sex =sex ;
26     }
27     public int getage() {
28 
29         return age;
30         }
31         public void setage(int age) {
32             // int a = Integer.parseInt(age);
33         this.age= age;
34         }
35 
36     public String getprovince() {
37         return province;
38     }
39     public void setprovince(String province) {
40         this.province=province ;
41     }
42 
43     public int compareTo(Student o) {
44        return this.name.compareTo(o.getName());
45     }
46 
47     public String toString() {
48         return  name+"\t"+sex+"\t"+age+"\t"+number+"\t"+province+"\n";
49     }    
50 }

 

 

l 采用结对编程方式,与学习伙伴合作完成实验十编程练习2。

 

package 运算;

import java.util.Scanner;

public class Demo {
	public static void main(String[] args) {
	// 用户的答案要从键盘输入,因此需要一个键盘输入流
@SuppressWarnings("resource")
	Scanner in = new Scanner(System.in);
	// 定义一个变量用来统计得分
int sum = 0;
	// 通过循环生成10道题
for (int i = 0; i < 10; i++) {

// 随机生成两个10以内的随机数作为被除数和除数
int a = (int) Math.round(Math.random() * 10);
	int b = (int) Math.round(Math.random() * 10);
	System.out.println(a + "/" + b + "=");
	// 定义一个整数用来接收用户输入的答案
int c = in.nextInt();
	// 判断用户输入的答案是否正确,正确给10分,错误不给分
if (c == a / b) {
	sum += 10;
	System.out.println("恭喜答案正确");
	}
else {
	System.out.println("抱歉,答案错误");
	}
	}
	//输出用户的成绩
System.out.println("你的得分为"+sum);
	}
}

package 运算;

public class Yuns {
	public int add(int a,int b)
 {
 return a+b;
 }
 public int reduce(int a,int b)
 {
 if((a-b)>0)
 return a-b;
 else return 0;
 }
 public int multiply(int a,int b)
 {
 return a*b;
 }
 public int devision(int a,int b)
 {
 if(b!=0)
 return a/b;
 else return 0;

}

学习总结:通过本周的学习,更懂得了Java的更多知识,也通过同学一起做一个实验时,更快地解决了自己没了解到的内容。

 

转载于:https://www.cnblogs.com/baimaciren/p/9930800.html

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