所以我有这个充满名字的链接列表。 用户将搜索名称的第一个字母,并打印出名称以字母开头的节点。 当我运行它时,它以为我没有得到任何回复。 虽然,如果我在循环中插入一些打印行,我会将它们取回。
在这里:
public String printSection(){
LinkedListNode current = front;
String searchedLetter;
int i = 0;
String retSec = "The nodes in the list are:n";
//Get the input of the name being removed
Scanner s = new Scanner(System.in);
System.out.println("Enter the first letter of the section you would like to print out");
searchedLetter = s.nextLine();
//while current is not null
while(current != null){
//if the data in current starts with the letter entered for searchedLetter
if(current.getData().startsWith(searchedLetter)){
//if(current.getData().substring(0,1) == searchedLetter){
//Increment the number of the node
i++;
//Print the node(s)
retSec += "Node " + i + " is: " + current.getData() + "n";
//Traverse the list
current = current.getNext();
System.out.println("You made it here");
}
}
return retSec;
}
}
这是:(新的工作方法)
public void printSection(){
LinkedListNode current = front;
String searchedLetter;
int i = 0;
//Get the input of the name being removed
Scanner s = new Scanner(System.in);
System.out.println("Enter the first letter of the section you would like to print out");
searchedLetter = s.nextLine();
//while current is not null
while(current != null){
//if the data in current starts with the letter entered for searchedLetter
if(current.getData().startsWith(searchedLetter)){
//Increment the number of the node
i++;
//Print the node
System.out.println("Node " + i + " is: " + current.getData());
}
//Traverse the list
current = current.getNext();
}
}
你在这里遇到了一个无休止的循环。
你只需要一个while循环,你必须跳到列表中的下一个元素,无论该元素是否以搜索的字母开头。
因此,请修改您的 if 语句并删除第二个 while 循环。还要确保始终转到下一个元素。
编辑:更深入地查看您的代码,我意识到您也没有检查您从用户那里请求的输入。他实际上不局限于单个字符,而是可以输入整行文本。因此,要么修复你给他的解释,要么引入对你的输入的验证(如果输入无效,包括一些错误消息)。