Introduction to Algorithms third Edition 10.2-4 Practice-Modify the list query method

Requirements:

As written, each loop iteration in the List-search ' procedure requires the tests:
One for X≠l.nil and one for x.key≠k. Show How to eliminate the test for
X≠l.nil in each iteration.

Solution:

The key is to set Sentinel Sentinel's key value to K prior to the start of the while loop, so that the while loop will terminate if the query succeeds in the list

Pseudo code

List-search ' (L, K)

1 L.nil.key = k

2 x = L.nil.next

3 while X.key≠k

4 x = X.next

5 if x = = L.nil

6 L.nil.key = Nil

7 return X

Introduction to Algorithms third Edition 10.2-4 Practice-Modify the list query method