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Computer Science

Posted by loxton
loxton
237 Points

Insert into Sorted Linked List Pseudocode

Does the following pseudocode accomplish inserting into a sorted linked list?

  • Input: a number a and a sorted linked list L of numbers
  • Output: a sorted list including a and L.
insertInSortedList(L,a)
1:      x = L.head
2:      while x ≠ NIL
3:      x = x.next
4:      if x.prev < a and x.next > a
1:      // Insert a into the linked list        
4:          x.next.prev = a
5:      x.next = a

1 Answer

Steven Parker
Steven Parker
229,708 Points
Steven Parker
Steven Parker
229,708 Points

It's not clear what the non-sequential numbers on the left side mean, and the lack of additional indentation makes it unclear which line(s) are part of the "while" loop.

Also, what if the value being added preceeds the very first (head) item, or should follow the very last (tail) item?