功能一：
package harrypotter;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.text.DecimalFormat;
public class HarryPotter1 {
static double a[][]=new double [52][2];
//static char b[]=new char [52];
static int number;
public static void main(String[] args) {
File file= new File("E:\java程序\Java24\src\harrypotter\Harry Potter and the Sorcerer's Stone.txt");
FileReader fr=null;
BufferedReader br=null;
try {
fr=new FileReader(file);
br=new BufferedReader(fr);
String str=null;
while((str=br.readLine())!=null)
{
//System.out.println(str);
char [] c=str.toCharArray();
//String b[]=new String[10000];
for(int i=0;i<str.length();i++)
{
int x=Integer.valueOf(c[i]);
if(x>=65&&x<=90)
{
a[x-65][1]++;
number++;
}
else if(x>=97&&x<=122)
{
a[x-97+26][1]++;
number++;
}
}
}
for(int j=0;j<52;j++)
{
if(j<26) a[j][0]=j+65;
else a[j][0]=j+97-26;
}
for (int i = 0; i<51; i++)
for (int j = 0; j < 51- i; j++)
{
if (a[j][1] < a[j + 1][1]) {
double temp = a[j][1];
a[j][1]= a[j + 1][1];
a[j + 1][1] = temp;
double m = a[j][0];
a[j][0]= a[j + 1][0];
a[j + 1][0] = m;
}
}
for (int j=0;j<52;j++)
{
double b=a[j][1]/number*100;
DecimalFormat df = new DecimalFormat("#.00");
System.out.println((char)(int)a[j][0]+":"+df.format(b)+"%");
}
} catch (Exception e) {
// TODO: handle exception
}
}
private static String df(double b) {
// TODO 自动生成的方法存根
return null;
}
}
功能二：
package harrypotter;
import java.io.*;
import java.util.*;
import java.util.Map.Entry;
public class HarryPotter
{
public static int n=0;
public static void main(String[] args) {
@SuppressWarnings("resource")
Scanner input=new Scanner(System.in);
int count=0;
int num=1;
String file1="E:\java程序\Java24\src\harrypotter\Harry Potter and the Sorcerer's Stone.txt1";
try
{
BufferedReader a=new BufferedReader(new FileReader(file1));
StringBuffer c=new StringBuffer();
String s;
while((s = a.readLine()) != null)
{
c.append(s);
}
String m=c.toString().toLowerCase();
String [] d=m.split("[^a-zA-Z0-9]+");
Map<String , Integer> myTreeMap=new TreeMap<String, Integer>();
for(int i = 0; i < d.length; i++) {
if(myTreeMap.containsKey(d[i])) {
count = myTreeMap.get(d[i]);
myTreeMap.put(d[i], count + 1);
}
else {
myTreeMap.put(d[i], 1);
}
}
List<Map.Entry<String, Integer>> list = new ArrayList<Map.Entry<String, Integer>>(myTreeMap.entrySet());
//按降序排序
Collections.sort(list, new Comparator<Map.Entry<String, Integer>>() {
public int compare(Entry<String, Integer> k1, Entry<String, Integer> k2) {
return k2.getValue().compareTo(k1.getValue());
}
});
System.out.println("请输入");
System.out.println("请输入N的值:");
n=input.nextInt();
for(Map.Entry<String, Integer> map : list) {
if(num <= n) {
System.out.println(map.getKey() + ":" + map.getValue());
num++;
}
else break;
}
a.close();
}
catch(FileNotFoundException e)
{
}
catch(IOException e)
{
}
}
}
}
一，建立一个二维数组，通过a~z,A~Z的ASSIC码确定各字母在二维数组中的位置，然后利用冒泡排序法对各数值进行排序