Exercise_1.py

# Python code to implement iterative Binary  
# Search. 
  
# It returns location of x in given array arr  
# if present, else returns -1 
# Time Complexity : O(log n)
# Space Complexity : O(1)
# Did this code successfully run on Leetcode : Yes
# Any problem you faced while coding this : No
def binarySearch(arr, l, r, x): 
  l, r = 0, len(arr)-1
  while l<=r:
     mid = (l+r)//2
     
     if arr[mid] == x:
      return mid
     elif arr[mid] < x:
      l = mid + 1
     else:
      r = mid-1
  return -1 
  
  
    
  
# Test array 
arr = [ 2, 3, 4, 10, 40 ] 
x = 10
  
# Function call 
result = binarySearch(arr, 0, len(arr)-1, x) 
  
if result != -1: 
    print ("Element is present at index % d" % result)
else: 
    print ("Element is not present in array")