Python: Binary search

Last update on August 19 2022 21:51:43 (UTC/GMT +8 hours)

Python Search and Sorting : Exercise-1 with Solution

Write a Python program for binary search.
Binary Search : In computer science, a binary search or half-interval search algorithm finds the position of a target value within a sorted array. The binary search algorithm can be classified as a dichotomies divide-and-conquer search algorithm and executes in logarithmic time.

Step by step example :

Sample Solution:

Python Code:

def binary_search(item_list,item):
	first = 0
	last = len(item_list)-1
	found = False
	while( first<=last and not found):
		mid = (first + last)//2
		if item_list[mid] == item :
			found = True
		else:
			if item < item_list[mid]:
				last = mid - 1
			else:
				first = mid + 1	
	return found
	
print(binary_search([1,2,3,5,8], 6))
print(binary_search([1,2,3,5,8], 5))

Sample Output:

False                                                                                                         
True

Flowchart:

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Python: Tips of the Day

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# Getting maximum from iterable
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>>> max(a)
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# Bot min/max has key value to allow to get maximum by appliing function
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