Binary Search | Python

 

#---------------------------->Recursive Binary Search.

def binarySearch(array, low,high,key):

if low <= high:

mid = low + (high - low) // 2

if array[mid] == key:

return mid

elif key > array[mid]:

return binarySearch(array,mid+1, high, key)

elif key < array[mid]:

return binarySearch(array,low,mid - 1,key)

else:

return -1

#--------------------------->Iterative Binary Search.

# def binarySearch(array, low, high, key):

# while low <= high:

# mid = low + (high - low)//2

# if array[mid] == key:

# return mid

# elif(array[mid] < key):

# low = mid + 1

# else:

# high = mid - 1

# return -1

if __name__ == "__main__":

array = [ 2, 3, 4, 10, 40 ]

print("Your array is: ", array)

key = int(input("Enter the key that you want to search: "))

res = binarySearch(array, 0,len(array)-1, key)

if res != -1:

print(f"Element found at {res+1} position.")

else:

print("Key not found")