Binary search python

Iterative binary search python

def binary_search(a, key):
	low = 0
	high = len(a) - 1
	while low < high:
		mid = (low + high) // 2
		if key == a[mid]:
			return True
		elif key < mid:
			high = mid - 1
		else:
			low = mid + 1

	return False

Binary search python

def binary_search(arr, item):
	first = 0
	last = len(arr) - 1
	while(first <= last):
		mid = (first + last) // 2
		if arr[mid] == item :
			return True
		elif item < arr[mid]:
			last = mid - 1
		else:
			first = mid + 1	
	return False

Binary search python

# This is real binary search
# this algorithm works very good because it is recursive

def binarySearch(arr, min, max, x):
    if max >= min:
        i = int(min + (max - min) / 2) # average
        if arr[i] == x:
            return i
        elif arr[i] < x:
            return binarySearch(arr, i + 1, max, x)
        else:
            return binarySearch(arr, min, i - 1, x)

Python binary search

#blog.icodes.tech
def binary_search(item,my_list):
    found=False
    first=0
    last=len(my_list)-1
    while first <=last and found==False:
        midpoint=(first+last)//2
        if my_list[midpoint]==item:
            found=True
        else:
            if my_list[midpoint]<item:
                first=midpoint+1
            else:
                last=midpoint-1
    return found

Source: blog.icodes.tech

Binary search in python

def binary_search_recursive(list_of_numbers, number, start=0, end=None):

    # The end of our search is initialized to None. First we set the end to the length of the sequence.
    if end is None:
        end = len(list_of_numbers) - 1

    if start > end:
        # This will happen if the list is empty of the number is not found in the list.
        raise ValueError('Number not in list')

    mid = (start + end) // 2  # This is the mid value of our binary search.

    if number == list_of_numbers[mid]:
        # We have found the number in our list. Let's return the index.
        return mid

    if number < list_of_numbers[mid]:
        # Number lies in the lower half. So we call the function again changing the end value to 'mid - 1' Here we are entering the recursive mode.



        return binary_search_recursive(list_of_numbers, number, start, mid - 1)
    # number > list_of_numbers[mid]
    # Number lies in the upper half. So we call the function again changing the start value to 'mid + 1' Here we are entering the recursive mode.

    return binary_search_recursive(list_of_numbers, number, mid + 1, end)

Source: stackoverflow.com

Binary search python

# Iterative Binary Search Function
# It returns index of x in given array arr if present,
# else returns -1
def binary_search(arr, x):
    low = 0
    high = len(arr) - 1
    mid = 0
 
    while low <= high:
 
        mid = (high + low) // 2
 
        # If x is greater, ignore left half
        if arr[mid] < x:
            low = mid + 1
 
        # If x is smaller, ignore right half
        elif arr[mid] > x:
            high = mid - 1
 
        # means x is present at mid
        else:
            return mid
 
    # If we reach here, then the element was not present
    return -1
 
 
# Test array
arr = [ 2, 3, 4, 10, 40 ]
x = 10
 
# Function call
result = binary_search(arr, x)
 
if result != -1:
    print("Element is present at index", str(result))
else:
    print("Element is not present in array")

Source: geeksforgeeks.org

Similar codes

-1 vote314 views1 answer
With urllib.request.urlopen("https://
Python
0 vote318 views1 answer
Ttk button
Python
-2 votes295 views9 answers
Django
Python Django
0 vote323 views1 answer
Type conversions in python
Python
0 vote332 views1 answer
Dataframe look at every second column
Python
0 vote350 views1 answer
Ascii to decimal python
Python
0 vote306 views1 answer
How to detect language python
Python
24 votes293 views2 answers
Python suppress warnings in function
Python
11 votes335 views2 answers
Find character in python
Python
25 votes305 views3 answers
Startapp django
Python