Count Set Bits in an Integer

Solving Approach:

1. Input Reading:
   • The program reads an integer n from the user using scanf.
2. Bitwise AND Operation:
   • Inside the countSetBits function, it checks the least significant bit (LSB) of n using (n & 0x01).
   • If the LSB is 1, it adds 1 to the count.
3. Bit Shifting:
   • The number n is right-shifted by one position using n = n >> 1 to process the next bit in the next loop iteration.
4. Loop Until Zero:
   • The loop continues until all bits have been processed (i.e., n becomes 0).
5. Output:
   • After counting all set bits, the result is printed using printf.

Code

#include <stdio.h>

int countSetBits(unsigned int n) {
    int count = 0;
    while(n){
        count = count + (n & 0x01);
        n = n >> 1;
    }
    return count;
}

int main() {
    int n;
    scanf("%d", &n);
    printf("%d\n", countSetBits(n));
    return 0;
}