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program to count zeros and ones in a binary number

program to count zeros and ones in a binary number

Write a C program to input a number from user and count total number of ones (1s) and zeros (0s) in the given number using bitwise operator. How to count zeros and ones in a binary number using bitwise operator in C programming.

    Input a number from user. Store it in some variable say j.
    Compute total bits required to store integer in memory i.e. INT_SIZE = sizeof(int) * 8.
    Initialize two variables to store zeros and ones count, say zeros = 0 and ones = 0.
    Run a loop from 0 to INT_SIZE. The loop structure should look like for(i=0; i<INT_SIZE; i++).
    Inside the loop check if Least Significant Bit of a number is set, then increment ones by 1 otherwise increment zeros by 1.
    Right shift j 1 time i.e. perform j = j >> 1;.

/* C program to count total of zeros and ones in a binary number using bitwise operator */

#include <stdio.h>
#define INT_SIZE sizeof(int) * 8 /* Total number of bits in integer */

int main()
{
    int j, zeros, ones, i;

    /* Input number from user */
    printf("Enter any number: ");
    scanf("%d", &j);

    zeros = 0;
    ones = 0;

    for(i=0; i<INT_SIZE; i++)
    {
        /* If LSB is set then increment ones otherwise zeros */
        if(j & 1)
            ones++;
        else
            zeros++;

        /* Right shift bits of j to one position */
        j >>= 1;
    }

    printf("Total zero bit is %d\n", zeros);
    printf("Total one bit is %d", ones);

    return 0;
}