Remove_N_after_M

const head1 = {
   val:1,
   next:{
      val:2,
      next:{
         val:3,
         next: {
            val:4,
            next:{
               val:5,
               next:null
            }
         }
      }
   }
}

const removeNafterM = (head, N, M) => {
   let counter = 1
   let ref = head
   while(counter < N)  {
      if(ref.next ===null){
         throw new Error('Starting point outside the list')
      }
      ref = ref.next
      counter++
   }

   secondRef = ref
   finalCounter = counter+M
   while(counter<=finalCounter) {
      if(secondRef.next === null){
         ref.next = null
         return head
      }
      secondRef = secondRef.next
      counter++
   }
   ref.next = secondRef;
   return head;
}
console.log(removeNafterM(head1,10,2));