reverseLinkedList.js

function reverseLinkedList(node) {
    var reversedPart = {
        data: null,
        next: null
    }
    var current = node;
    while(current) {
        let nextNode = current.next;
        current.next = reversedPart;
        reversedPart = current;
        current = nextNode;
    }
    console.log("result is ", reversedPart)
    return reversedPart;
}

reverseLinkedList({data: 2, next: {data: 4, next: {data: 5, next: {data: 12, next:null}}}});