nodeEnthu

var mergeTwoLists = function(l1, l2) {
    const newNode = new ListNode(-1);
    
    function mergeTwoListsRec(newL1Head, newL2Head, prevHead) {
        
        if(!newL1Head || !newL2Head) {
            prevHead.next = (newL1Head || newL2Head);
            return;
        }
        

nodeEnthu

intersectionCallback(entries, observer) {
    const self = this;
    entries.forEach(entry => {
      if(entry.isIntersecting) {
        // append the current row in visible area
        const divToAppendReactElement = document.createElement('div');
        divToAppendReactElement.id = `dom${this.currentScrollPosition}`;
        const newElement = ReactDOM.render(self.configureInsertedElement(), divToAppendReactElement);
        const parentNode = entry.target.parentNode;
        const target = document.getElementById(`end-sentinel${this.currentScrollPosition}`);