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@ajaysusarla
Created July 12, 2016 13:17

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  1. ajaysusarla created this gist Jul 12, 2016.
    27 changes: 27 additions & 0 deletions count_bits.c
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,27 @@
    #include <stdint.h>
    #include <limits.h>

    #define numbits(x) (sizeof(x) * 8)

    #define max_signed_value_of_type(t) \
    (INTMAX_MAX >> (numbits(intmax_t) - numbits(t)))

    void count_bits(unsigned int num)
    {
    size_t bits = numbits(num);
    unsigned int max = max_signed_value_of_type(num) + 1;
    int i;
    unsigned int t = num;
    int zeroes = 0, ones = 0;

    for (i = 0; i < bits; i++) {
    if (!!(num & max))
    ones++;
    else
    zeroes++;

    num = num << 1;
    }

    printf("%u has %d 0's and %d 1's in its binary representation.\n", t, zeroes, ones);
    }