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Thread: lookup method in a sorted linked list

  1. #1
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    Join Date
    Apr 2020
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    Default lookup method in a sorted linked list

    Okay this should be the final post about this God forbidden topic.So i need to implement this following method.

     
    public Person lookup(String name) {
    		if(head == null) {
    			return null;
    		}
    		if(head.person.name.compareTo(name) == 0) {
    			head = head.next;
    			return person;
    		}
     
    		Node current = head;
    		Node prev = head;
    		while(current != null) {
    			if(current.person.name.compareTo(name) == 0) {
    				prev.next = current.next;
    				return person;
    			}
    			prev = current;
    			current = current.next;
    		}
    		return null;
    	}

    Now the idea behind this is to go through the list checking for the parameter name and if we find a match return the person with that name.I think I did the "travesing" or going through the list part corectly, but the issue is the return value.When nothing is found null; makes sence.But if we find the person we need to return it. The return person here doesn't work I get this error:
    PhoneBookList.java:92: error: cannot find symbol
    return person;
    ^
    symbol: variable person
    location: class PhoneBookList
    PhoneBookList.java:100: error: cannot find symbol
    return person;
    ^
    symbol: variable person
    location: class PhoneBookList
    2 errors

    Any help? Thanks


    EDIT: Okay I've figured it out actually,
     
    public Person lookup(String name) {
     
            if (head == null) { 
                return null;
            }
     
            Node current = head;  
            while (current != null) {
                if (current.person.name.compareTo(name)==0) { 
                    return current.person;
                }
                current = current.next; 
            }
            return null;
        }
    Should work
    Last edited by arhzz; May 16th, 2020 at 02:00 PM.

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