Check if bits in range L to R of two numbers are complement of each other or not in Python

PythonServer Side ProgrammingProgramming

Suppose we have two numbers x and y and a given range (left, right). We have to check whether all bits in range left to right in both the given numbers are complement of each other or not. We have to keep in mind that from right to left, so the least significant bit is considered to be at first position.

So, if the input is like x = 41 y = 54 left = 2 right = 5, then the output will be True, as binary representation of 41 and 54 are 101001 and 110110. The bits in range 2 to 5 of x and y are "1001" and "0110" which are complement of each other.

To solve this, we will follow these steps −

  • temp := x XOR y
  • return true when all bits in range (left, right) of temp is 1, otherwise false

Let us see the following implementation to get better understanding −


 Live Demo

def are_all_setbits_in_range(n, left, right):
   val = ((1 << right) - 1) ^ ((1 << (left - 1)) - 1)
   new_value = n & val
   if val == new_value:
      return True
   return False
def solve(x, y, left, right):
   temp = x ^ y
   return are_all_setbits_in_range(temp, left, right)
x = 41
y = 54
left = 2
right = 5
print(solve(x, y, left, right))


41, 54, 2, 5


Published on 30-Dec-2020 17:57:49