var mergeTwoLists = function(list1, list2) {
let l1,l2,l3,head3;
[l1, l2, head3] = [list1, list2, new ListNode(0)];
l3 = head3;
while(l1 && l2) {
if( l1.val >= l2.val ) {
l3.next = l2;
l2 = l2.next;
}else {
l3.next = l1;
l1 = l1.next;
}
l3 = l3.next;
}
l3.next = l1 || l2;
return head3.next;
};
mergeTwoLists([1,2,4],[1,3,4]);


I noticed this javascript code produces "Uncaught ReferenceError: ListNode is not defined at mergeTwoLists " which is coming from the third line when I try running it on my text editor but run's well on leetcode javascript editor
1. Please I want to know why the code is working on leetcode text editor and not working on the usual text editor.
2. Please I also need explanation on how l1.val, l2.val,l3.next,l2.next and l1.next properties are not returning un define. Because to the best of my understanding regular array does not have those value

try paste this on stackoverflow for quick solutions

ListNode should be defined by LeetCode, there is debug code in playground button where the ListNode is defined by LeetCode

CC: Stackoverflow

It is not defined because you haven't created the linked list data structure. You are running it outside leetcode which gives you the data structure defined.

efelico:
var mergeTwoLists = function(list1, list2) {
let l1,l2,l3,head3;
[l1, l2, head3] = [list1, list2, new ListNode(0)];
l3 = head3;
while(l1 && l2) {
if( l1.val >= l2.val ) {
l3.next = l2;
l2 = l2.next;
}else {
l3.next = l1;
l1 = l1.next;
}
l3 = l3.next;
}
l3.next = l1 || l2;
return head3.next;
};
mergeTwoLists([1,2,4],[1,3,4]);


I noticed this javascript code produces "Uncaught ReferenceError: ListNode is not defined at mergeTwoLists " which is coming from the third line when I try running it on my text editor but run's well on leetcode javascript editor
1. Please I want to know why the code is working on leetcode text editor and not working on the usual text editor.
2. Please I also need explanation on how l1.val, l2.val,l3.next,l2.next and l1.next properties are not returning un define. Because to the best of my understanding regular array does not have those value

Try to study and understand the code first.Where is your ListNode class? So u dont know the “new list ode(0)” is instance of a class called list node which might be an implementation of a linked list. So where is the class?

chukwuebuka65:


Try to study and understand the code first.Where is your ListNode class? So u dont know the “new list ode(0)” is instance of a class called list node which might be an implementation of a linked list. So where is the class?

Probably a copy paste solution.

GREATIGBOMAN:


Probably a copy paste solution.

I thought as much.

tensazangetsu20:
It is not defined because you haven't created the linked list data structure. You are running it outside leetcode which gives you the data structure defined.

Thank you

chukwuebuka65:


Try to study and understand the code first.Where is your ListNode class? So u dont know the “new list node(0)” is instance of a class called list node which might be an implementation of a linked list. So where is the class?

I actually copied the code. What I am saying is that for the exact code to run on leetcode and not run on an ide is something else. This same code is working without listnode class being define on leetcode that is why I was asking.


However Tensa comment has helped to clarify me

tensazangetsu20:
It is not defined because you haven't created the linked list data structure. You are running it outside leetcode which gives you the data structure defined.

.

eaimiesylv:



I actually copied the code. What I am saying is that for the exact code to run on leetcode and not run on an ide is something else. This same code is working without listnode class being define on leetcode that is why I was asking.


However Tensa comment has helped to clarify me
.

Ok

I have solved this one bf.

I used shift and pop and a while loop.

efelico:
var mergeTwoLists = function(list1, list2) {
let l1,l2,l3,head3;
[l1, l2, head3] = [list1, list2, new ListNode(0)];
l3 = head3;
while(l1 && l2) {
if( l1.val >= l2.val ) {
l3.next = l2;
l2 = l2.next;
}else {
l3.next = l1;
l1 = l1.next;
}
l3 = l3.next;
}
l3.next = l1 || l2;
return head3.next;
};
mergeTwoLists([1,2,4],[1,3,4]);


I noticed this javascript code produces "Uncaught ReferenceError: ListNode is not defined at mergeTwoLists " which is coming from the third line when I try running it on my text editor but run's well on leetcode javascript editor
1. Please I want to know why the code is working on leetcode text editor and not working on the usual text editor.
2. Please I also need explanation on how l1.val, l2.val,l3.next,l2.next and l1.next properties are not returning un define. Because to the best of my understanding regular array does not have those value

Regarding your second question, I don’t think the input is an array. It should be a linked list containing those values. Even though it was written as an array, it just a way to give you an example of an input and the expected output. Even from the name “mergeList”, you should know the function expects a linked list.

chukwuebuka65:


Regarding your second question, I don’t think the input is an array. It should be a linked list containing those values. Even though it was written as an array, it just a way to give you an example of an input and the expected output. Even from the name “mergeList”, you should know the function expects a linked list.

Thank you