This is a Python program to count set bits in a number.

The program finds the number of ones in the binary representation of a number.

1. Create a function count_set_bits that takes a number n as argument.

2. The function works by performing bitwise AND of n with n – 1 and storing the result in n until n becomes 0.

3. Performing bitwise AND with n – 1 has the effect of clearing the rightmost set bit of n.

4. Thus the number of operations required to make n zero is the number of set bits in n.

Here is the source code of a Python program count set bits in a number. The program output is shown below.

def count_set_bits(n): count = 0 while n: n &= n - 1 count += 1 return count n = int(input('Enter n: ')) print('Number of set bits:', count_set_bits(n))

1. The user is asked to input n.

2. The number of set bits is found by calling count_set_bits on n.

Case 1: Enter n: 9 Number of set bits: 2 Case 2: Enter n: 31 Number of set bits: 5 Case 3: Enter n: 1 Number of set bits: 1

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