Give My Text Back

Give My Text Back

标签（空格分隔）： 算法

时间限制:10000ms

单点时限:1000ms

内存限制:256MB

描述

To prepare for the English exam Little Ho collected many digital reading materials. Unfortunately the materials are messed up by a malware.

It is known that the original text contains only English letters (a-zA-Z), spaces, commas, periods and newlines, conforming to the following format:

Each sentence contains at least one word, begins with a letter and ends with a period.

In a sentence the only capitalized letter is the first letter.

In a sentence the words are separated by a single space or a comma and a space.

The sentences are separated by a single space or a single newline.

It is also known the malware changes the text in the following ways:

Changing the cases of letters.

Adding spaces between words and punctuations.

Given the messed text, can you help Little Ho restore the original text?

输入

A string containing no more than 8192 English letters (a-zA-Z), spaces, commas, periods and newlines which is the messed text.

输出

The original text.

样例输入

my Name is Little Hi.

His name IS Little ho , We are friends.

样例输出

My name is little hi.

His name is little ho, we are friends.

解析

规则：

每个标点符号之前没有空格，标点符号之后加空格；

‘.’之后表示每个句子的开始，首字母应该大写；

只有每个句子的句首字母应该大写；

代码：

import java.util.Scanner;
public class Main {
public static String dealwith(String s) {
String s1 = s.trim().toLowerCase();
char[] ch = s1.toCharArray();
ch[0] = Character.toUpperCase(ch[0]);
StringBuffer sb = new StringBuffer();
boolean flag = false;
for(int i=0; i<ch.length; i++) {
if( ch[i] <= 'z' && ch[i] >= 'A') { //正常的字符
if(flag == true) {
sb.append(Character.toUpperCase(ch[i]));
flag = false;
}
else
sb.append(ch[i]);
}
else if(ch[i] == ' ') { //如果是空格，分两种情况
if(sb.charAt(sb.length()-1) != ' ')
sb.append(" ");
else
continue;
}
else { //是标点符号
if(ch[i] == '.')
flag = true;
if(sb.charAt(sb.length()-1) == ' ') { //如果标点前有空格，则删除
sb.deleteCharAt(sb.length()-1);
sb.append(ch[i]);
sb.append(" ");
}
else {
if(i == ch.length-1) //如果是最后一个字符
sb.append(ch[i]);
else {
sb.append(ch[i]);
sb.append(" ");
}
}
}

}
return sb.toString();
}

public static void main(String[] args) {
// TODO Auto-generated method stub
Scanner sc = new Scanner(System.in);
while(sc.hasNext()) {
String s = sc.nextLine();
String res = dealwith(s);
System.out.println(res);
}
}

}