回文问题，求助

[StayHungry]

class TJ4_5{
public static void main(String args[]){
String s="Madam I'm Adam",s2,s3,s4;
char a[]=s.toCharArray(),temp;
char s1[]=new char[s.length()];
char c[]=new char[s.length()];
char d[]=new char[s.length()];
for(int i=0;i<s.length();i++){
if(Character.isLetterOrDigit(a[i])){
s1[i]=a[i];
}
}
s2=new String(s1);
if(s2.length()%2==0){
s2.getChars(0,s2.length()/2,c,0);
s2.getChars(s2.length()/2,s2.length(),d,0);
System.out.println(c); //交换前的c字符串
System.out.println(d); //交换前的c字符串
}
else{
s2.getChars(0,s2.length()/2,c,0);
s2.getChars(s2.length()/2+1,s2.length(),d,0);
System.out.println(c); //交换前的c字符串
System.out.println(d); //交换前的d字符串
}
for(int i=0;i<d.length/2;i++){
temp=d[i];
d[i]=d[d.length-i-1];
d[d.length-i-1]=temp;
}
s3=new String(c);
s4=new String(d);
System.out.println(s4);
if(s3.equalsIgnoreCase(s4)){
System.out.println("是回文");
}
else{
System.out.println("不是回文");
}
}
}
这个程序在字符串转化为数组之后，数组长度一直是14（字符串的长度），为什么在把a数组赋给s1数组之后长度还是没有变化？请问应该如何更改程序，才能是结果正常？

[BlueSunny]

你结果是要做什么呢？说实话对字符串数字奇偶的判别处想要作什么不是很清楚
如果是回文处理，逆序字符串即可做到啊

[JhunHoonXZ]

char c[]=new char[s.length()];
char d[]=new char[s.length()];
这是长度不变化的原因~

你这个方法实在是..不想改..重新写个新的好了

class TJ4_5 {
	public static void main(String args[]) {
		String s = "Madam I'm Adam";
		String s1 = new String();
		String s2 = new String();
		char a[] = s.toCharArray();
		for (int i = 0; i < a.length; i++)
			if (Character.isLetterOrDigit(a[i])) {
				s1 = s1 + a[i];
				s2 = a[i] + s2;
			}
		if (s1.equalsIgnoreCase(s2))
			System.out.println("是回文");
		else
			System.out.println("不是回文");
	}
}

[JhunHoonXZ]

不变化的原因:
char s1[]=new char[s.length()];
晕,就这行没复制上...

s1你已经声明了数组长度是14
那么我只给前3个赋值..长度还是14,只不过后面的都是空的而已..

[cwjieNo5]

修改了一下`
[code=Java]import java.awt.*;
public class HuiWen {

/**
* @langzi
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String str = "aabbcc";
String s1 = new String();
String s2 = new String();
char c[] = str.toCharArray();
for(int i = 0 ; i < str.length();i++){
if(Character.isLetterOrDigit(c[i])){
s1 = s1 + c[i];
s2 = c[i] + s2;
}
s1 = new String(s1);
s2 = new String(s2);
}
if(s1.equalsIgnoreCase(s2)){
System.out.println("is huiwen");
}
else
System.out.println("is not huiwen");
}
}
[/java]

[cwjieNo5]

修改了一下`
[code=Java]import java.awt.*;
public class HuiWen {

/**
* @langzi
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
String str = "aabbcc";
String s1 = new String();
String s2 = new String();
char c[] = str.toCharArray();
for(int i = 0 ; i < str.length();i++){
if(Character.isLetterOrDigit(c[i])){
s1 = s1 + c[i];
s2 = c[i] + s2;
}
s1 = new String(s1);
s2 = new String(s2);
}
if(s1.equalsIgnoreCase(s2)){
System.out.println("is huiwen");
}
else
System.out.println("is not huiwen");
}
}
[/java]