Python Program to Find the Number of Bits Required to Represent an Integer in Binary

Learn how to write a Python program that calculates the number of bits needed to represent an integer in binary format. Follow the step-by-step instructions and example code to gain a clear understanding of the logic behind the program.

Problem

Write a Python program that takes an integer as input and outputs the number of bits needed to represent that integer in binary format.

Example Code

def num_bits(n):
    """
    Calculates the number of bits required to represent an integer in binary format.
    """
    count = 0
    while n > 0:
        count += 1
        n >>= 1
    return count

# Example usage
print(num_bits(10))  

Expected output

 4

Explanation:

The program defines a function num_bits() that takes an integer n as input. The function initializes a counter variable count to 0 and enters a while loop that continues until n is 0.

During each iteration of the loop, the function increments count by 1 and right-shifts n by 1 bit. The right-shift operation removes the least significant bit from n, and when n becomes 0, the loop exits and the function returns count.

To test the function, the program calls num_bits() with an example integer value of 10 and prints the result to the console. The expected output is 4 since 10 in binary format requires 4 bits to represent.