Implementing binary search

In this video, you learned how to implement linear search and binary search and saw the differences between them.

In this exercise, you need to implement the binary_search() function. Can you do it?

This exercise is part of the course

Data Structures and Algorithms in Python

View Course

Exercise instructions

Check whether the search value equals the value in the middle.
Check whether the search value is smaller than the value in the middle
Set last to the value of middle minus one.

Hands-on interactive exercise

Have a go at this exercise by completing this sample code.

def binary_search(ordered_list, search_value):
  first = 0
  last = len(ordered_list) - 1
  
  while first <= last:
    middle = (first + last)//2
    # Check whether the search value equals the value in the middle
    if ____ == ____:
      return True
    # Check whether the search value is smaller than the value in the middle
    elif ____ < ____:
      # Set last to the value of middle minus one
      ____
    else:
      first = middle + 1
  return False
  
print(binary_search([1,5,8,9,15,20,70,72], 5))

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