InsertTo_Sorted__OneLink_LinkedList.js

function Node(data) {
  this.data = data;
  this.next = null;
}
function sortedInsert(head, data) {  
  let currentNode = head;
  let prevNode = head;
  const target = new Node(data);
  
  // insert in begining;
  if(!head || target.data < head.data){
    target.next = head;
    return target;   
  }
  
  // insert in middle
  while(currentNode !== null){
    if(currentNode.data > target.data){      
      prevNode.next = target;
      target.next = currentNode;
      return head;
    }
    prevNode = currentNode;
    currentNode = currentNode.next;    
  }
  
  // insert in end;
  prevNode.next = target;
  return head;
}