关于活动的题，有点小疑问 - 黑马程序员技术交流社区

import java.util.*;
public class Test14
{
public static void main(String []args){
String str=StringTool.containString("ahellodsaf");
System.out.println(str);
StringTool.StringCount(str);
}
}
class StringTool
{
public static String containString(String s2){
String s1="sdfg,hellozx,sdfcv-waadfa,fsasdfxcvdf";
String xs=null;
flag:
for(int i=0;i<s1.length();i++){
for(int start=0,end=s1.length()-i;end!=s1.length()+1;start++,end++){
String temp=s1.substring(start,end);
if(s2.contains(temp)){
//System.out.println(temp);
xs=s1.substring(0,start)+""+s1.substring(end,s1.length());
//System.out.println(xs);
break flag;
}
}
}
return xs;
}
public static void StringCount(String str){
char []a=str.toCharArray();
Map<Character,Integer> map=new HashMap<Character,Integer>();
for(int i=0;i<a.length;i++){
if(a[i]>'a'&&a[i]<'z'||a[i]>'A'&&a[i]<'Z'){
if(map.containsKey(a[i])){
int temp=map.get(a[i]);
temp+=1;
map.put(a[i],temp);
}else{
map.put(a[i],1);
}
}
}
StringBuilder sb=new StringBuilder();
//这一块想实现排序，可是我又理解Map.Entry<String,Integer>不是很深刻，所以处理起来有问题了
//下面这段被我注释的代码有问题，求高手指点，那里修改后，就可以正常输出排序后的结果
/*List<Map.Entry<String,Integer>> list=new ArrayList<Map.Entry<String,Integer>>();
list.addAll(map.entrySet());
Collections.sort(list,new Comparator<Map.Entry<String,Integer>>(){
public int compare(Map.Entry<String,Integer> o1,Map.Entry<String,Interger> o2){
return o1.getValue()-o2.getValue();
}
});
System.out.println(list);
*/
Set<Map.Entry<Character,Integer>> entryset=map.entrySet();
Iterator<Map.Entry<Character,Integer>> it=entryset.iterator();
while(it.hasNext()){
Map.Entry<Character,Integer>ch=it.next();
Character key=ch.getKey();
Integer value=ch.getValue();
sb.append(key+"("+value+")");
}
System.out.println(sb);
}
}

复制代码

import java.io.*;
import java.util.*;
class dayDemo
{
public static String str1 = "sdfg,hellozx,sdfcv-waadfa,fsasdfxcvdf";
public static StringBuilder sb = new StringBuilder(str1);
public static void main(String []args) throws Exception{
String str2 = input();
String maxlenword = getMaxWord(sb,str2);
String fixstr1 = delStr(sb,maxlenword);
countChar(fixstr1);
}
public static String input() throws Exception{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String str2 = br.readLine();
br.close();
return str2;
}
public static String getMaxWord(StringBuilder s1,String s2){
ArrayList<String> list=new ArrayList<String>();
for(int i=0;i<s1.length();i++){
for(int j=i+2;j<=s1.length();j++){
String str=s1.substring(i,j);
if(s2.indexOf(str)!=-1){
list.add(str);
}
}
}
int maxlen = 0;
int maxlenword =0;
for(int i=0;i<list.size();i++){
if(maxlen<list.get(i).length()){
maxlen = list.get(i).length();
maxlenword = i;
}
}
return list.get(maxlenword);
}
public static String delStr(StringBuilder str1,String maxlenword){
int pos = 0;
while(sb.toString().contains(maxlenword)){
pos = sb.toString().indexOf(maxlenword);
sb.delete(pos,maxlenword.length()+pos);
}
return sb.toString();
}
public static void countChar(String fixstr1){
char []c = fixstr1.toCharArray();
TreeMap<Character,Integer> tm = new TreeMap<Character,Integer>();
for(int i=0;i<c.length;i++){
int count = 1;
for(int j=0;j<c.length;j++){
if(c[i]==c[j]&&(c[i]>'A'&&c[i]<'z')){
tm.put(c[i],count++);
}
}
}
List<Map.Entry<Character,Integer>> entryLists = new ArrayList<Map.Entry<Character,Integer>>(tm.entrySet());
Collections.sort(entryLists, new EntryComparator());
for(Map.Entry<Character, Integer> entry : entryLists) {
System.out.print(entry.getKey()+"(出现" + entry.getValue()+"次)");
}
}
}
class EntryComparator implements Comparator<Map.Entry<Character, Integer>>
{
public int compare(Map.Entry<Character, Integer> map1,Map.Entry<Character, Integer> map2){
int num = map2.getValue() - map1.getValue();
if(num==0)
return map2.getKey().toString().compareTo(map1.getKey().toString());
return map2.getValue() - map1.getValue();
}
}

复制代码

List<Map.Entry<Character,Integer>> list=new ArrayList<Map.Entry<Character,Integer>>(entryset);//把关系类放到List集合中。

复制代码

import java.util.*;
class TreeMapDemo
{
public static void main(String[] args)
{
TreeMap<Character,Integer> tm = new TreeMap<Character,Integer>();
tm.put('a', 1);
tm.put('c', 3);
tm.put('y', 6);
tm.put('f', 3);
Set<Map.Entry<Character,Integer>> entryset = tm.entrySet();
List<Map.Entry<Character,Integer>> enlist = new ArrayList<Map.Entry<Character,Integer>>(entryset);//注意这里
Collections.sort(enlist,new IntegerDemo()); //Collections.sort是用在List集合中的。
Iterator<Map.Entry<Character,Integer>> it = enlist.iterator();
while(it.hasNext())
{
Map.Entry<Character,Integer> me = it.next();
Character c = me.getKey();
Integer i = me.getValue();
System.out.println(c+":"+i);
}
}
}
class IntegerDemo implements Comparator<Map.Entry<Character,Integer>>
{
public int compare(Map.Entry<Character,Integer> c1,Map.Entry<Character,Integer> c2)
{
return c2.getValue().compareTo(c1.getValue());
}
}

复制代码

import java.util.*;
public class Test14
{
public static void main(String []args){
String str=StringTool.containString("ahellodsaf");
System.out.println(str);
StringTool.StringCount(str);
}
}
class StringTool
{
public static String containString(String s2){
String s1="sdfg,hellozx,sdfcv-waadfa,fsasdfxcvdf";
String xs=null;
flag:
for(int i=0;i<s1.length();i++){
for(int start=0,end=s1.length()-i;end!=s1.length()+1;start++,end++){
String temp=s1.substring(start,end);
if(s2.contains(temp)){
//System.out.println(temp);
xs=s1.substring(0,start)+""+s1.substring(end,s1.length());
//System.out.println(xs);
break flag;
}
}
}
return xs;
}
public static void StringCount(String str){
char []a=str.toCharArray();
Map<Character,Integer> map=new TreeMap<Character,Integer>();
for(int i=0;i<a.length;i++){
if(a[i]>'a'&&a[i]<'z'||a[i]>'A'&&a[i]<'Z'){
if(map.containsKey(a[i])){
int temp=map.get(a[i]);
temp+=1;
map.put(a[i],temp);
}else{
map.put(a[i],1);
}
}
}
//*************************************************************
//一下是按照楼主的思路修改的。
Set<Map.Entry<Character,Integer>> me = map.entrySet();
StringBuilder sb=new StringBuilder();
List<Map.Entry<Character,Integer>> list=new ArrayList<Map.Entry<Character,Integer>>();
list.addAll(me);
Collections.sort(list,new MyComparator());//匿名内部类太乱，最起码我看着不爽，所以我把比较器拿出来
//单独封装成了类MyComparator，作用是实现按照值来排序
System.out.println(list);//输出按值比较后的list列表
Iterator<Map.Entry<Character,Integer>> it=list.iterator();
while(it.hasNext()){
Map.Entry<Character,Integer>ch=it.next();
Character key=ch.getKey();
Integer value=ch.getValue();
sb.append(key+"("+value+")");
}
System.out.println(sb);
}
}
class MyComparator implements Comparator<Map.Entry<Character,Integer>>
{
public int compare(Map.Entry<Character,Integer> me1,Map.Entry<Character,Integer> me2)
{
//按值来比较，me2放前面，按照从大到小排列
int num = new Integer(me2.getValue()).compareTo(new Integer(me1.getValue()));
if(num==0)
return me2.getKey().compareTo(me1.getKey());//当值相同时，按键比较
return num;
}
}

复制代码