def binarySearch (arr, l, r, x): 
  
    # Check base case 
    if r >= l: 
  
        mid = l + (r - l)/2
  
        # If element is present at the middle itself 
        if arr[int(mid)] == x: 
            return mid 
          
        # If element is smaller than mid, then it  
        # can only be present in left subarray 
        elif arr[int(mid)] > x: 
            return binarySearch(arr, l, int(mid)-1, x) 
  
        # Else the element can only be present  
        # in right subarray 
        else: 
            return binarySearch(arr, int(mid) + 1, r, x) 
  
    else: 
        # Element is not present in the array 
        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 " + str(result)) 
else: 
    print ("Element is not present in array")


def PowerOfTwo(num):
    if (num == 0): 
        return False
    while (num != 1): 
            if (num % 2 != 0): 
                return False
            n = n // 2
    return True

print(PowerOfTwo(9))