Question

这是我在这里的第一篇文章，顺便说一下，我的老师给了班级编程的任务，我们需要做一个回文程序，我能够做到但我想摆脱错误，你能解释一下为什么会有错误，我该如何摆脱它？

import java.io.*;

public class AssignmentInCopro 

{public static void main (String [] args) throws IOException
    {BufferedReader x = new BufferedReader(new InputStreamReader(System.in));

    String word = "";

    System.out.print("Please enter the word you want to see in reverse: ");
    word = x.readLine();

    int wordLength = word.length(); 

    while (wordLength >=0)
    {
    char letter = word.charAt(wordLength - 1);
    System.out.print(letter);
    wordLength--;
    }
    }
}

Answer 1

当你的循环包含索引零时，会出现错误。如果wordLength为零，那么您将查找charAt(-1)并获得例外：

将您的代码更改为：

while (wordLength >0)

错误消失了。

Answer 2

 while (wordLength >=0)

当wordLength = 0时会导致错误，那么char letter = word.charAt(wordLength - 1);实际上是char letter = word.charAt(0 - 1);

while (wordLength >0)

这应该是条件，或者你可以像这样编写你的循环 -

int wordLength = word.length() - 1;
while (wordLength >=0){
    System.out.print(word.charAt(wordLength--));
}

Answer 3

看看当wordlength实际上等于0时会发生什么// while（wordLength＆gt; = 0）你试图在-1 //word.charAt(wordLength - 1）;

访问char

用while（wordLength＆gt; 0）或while（wordLength＆gt; = 1）更改它

度过愉快的一天

程序正在运行，但有错误，字符串索引超出范围：-1

3 个答案: