java作业16027240048

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作业1
P159.11

Text:import java.util.HashMap;import java.util.Map;import java.util.Set;public class Text {    private String name;    private int salary;    Text(String a, int b) {        name = a;        salary = b;    }    public String getName() {        return name;    }    public int getSalary() {        return salary;    }    public void setName(String name) {        this.name = name;    }    public void setSalary(int salary) {        this.salary = salary;    }    public static void main(String args[]) {        HashMap<String, Integer> hashMap = new HashMap<String, Integer>();        hashMap.put("张三", 8000);        hashMap.put("李四", 6000);        Set<Map.Entry<String,Integer>> set = hashMap.entrySet();//转换成set用迭代器遍历        for(Map.Entry<String,Integer>entry : set){            System.out.println(entry.getKey()+":"+entry.getValue());        }        hashMap.put("张三",8500);        for(Map.Entry<String,Integer>entry : set){            System.out.println(entry.getKey()+":"+entry.getValue());        }    }}

12

Text2:import java.lang.*;public class Text2 implements Comparable{    private String name;    private int salary;    Text2(String a,int b){        name = a;        salary = b;    }    public String getName() {        return name;    }    public int getSalary() {        return salary;    }    public void setName(String name) {        this.name = name;    }    public void setSalary(int salary) {        this.salary = salary;    }    public int compareTo(Object p) {        Text2 p1 = (Text2) p;        if(this.salary>p1.salary){            return -1;        }        else{            return 1;        }    }}测试类：import java.util.*;import java.lang.*;public class Text02 {    public static void main(String args[]){        Set<Text2> set =new TreeSet<Text2>();        Text2 p1 = new Text2("张三",8000);        Text2 p2 = new Text2("李四",6000);        Text2 p3 = new Text2("王五",5600);        Text2 p4 = new Text2("马六",7500);        set.add(p1);        set.add(p2);        set.add(p3);        set.add(p4);        for(Text2 p :set){            System.out.println(p.getName()+":"+p.getSalary());        }    }}

13

import java.util.*;public class Customer {    private String name;    private int age;    private String gender;    Customer(String a,int b,String c){        name = a;        age = b;        gender = c;    }    public String getName() {        return name;    }    public int getAge() {        return age;    }    public String getGender() {        return gender;    }    public void setName(String name) {        this.name = name;    }    public void setAge(int age) {        this.age = age;    }    public void setGender(String gender) {        this.gender = gender;    }    public static void main(String args[]){        Customer s1 = new Customer("张立",18,"女");        Customer s2 = new Customer("王猛",22,"男");        List<Customer> arrayList = new ArrayList();        arrayList.add(s1);        arrayList.add(s2);        for(Customer cu : arrayList){            System.out.println(cu.name);            System.out.println(cu.age);            System.out.println(cu.gender);        }    }}

14

import java.util.*;import java.lang.*;public class Text17 {    public static void main(String args[]){        String s = "today is a specil day";        int a[] = new int [100];        for(int i = 0;i<26;i++) {            a[i] = 0;        }        Map<Character,Integer> map= new HashMap<Character,Integer>();        int max1 = 0;        Character max2 = null;        for(int i = 0;i<s.length();i++){            if(s.charAt(i)!=' ') {                a[s.charAt(i)-'a']++;                if(a[s.charAt(i)-'a']>max1) {                    max1 = a[s.charAt(i)-'a'];                    max2 =s.charAt(i);                }                map.put(s.charAt(i),a[s.charAt(i)-'a']);            }        }        System.out.printf("数量最多的字符是:%c:%d",max2, max1);    }}

作业2

import java.util.*;public class Text18 {    public static void main(String args[]){        Random random = new Random();        Set<Integer>set = new TreeSet<Integer>();        for(int i = 0;i<50;i++){            set.add(random.nextInt(100));        }        System.out.println(set);    }}

作业3

import java.util.*;public class Text19 {    public static void main(String args[]) {        Map<String, String[]> map = new HashMap<String, String[]>();        String[] sd = {"济南", "济宁", "青岛", "烟台", "胶州", "威海", "等等"};        String[] hb = {"石家庄", "唐山", "廊坊", "沧州", "等等"};        String[] ln = {"沈阳", "等等"};        map.put("山东", sd);        map.put("河北",hb);        map.put("辽宁",ln);        Scanner sc = new Scanner(System.in);        String s1  = sc.next();        while(true){            if(s1.equals("退出"))            break;            else{                Set<String> set  = map.keySet();                Iterator<String> iter = set.iterator();                while(iter.hasNext()){                    String s2 = iter.next();                    if(s2.equals(s1)){                        String s3[] = map.get(s2);                        for(int i = 0;i<s3.length;i++) {                            System.out.println(s3[i]);                        }                    }                }                break;            }        }    }}