C Program to Reverse all the Bits of an 32-bit Integer using Bitwise

/*
 * C Program to Reverse all the Bits of an 32-bit Integer using
 * Bitwise
 */
#include <stdio.h>
#define NUM_BITS_INT sizeof(int)*8

void main()
{
    unsigned int number;
    int i = 0, hexadecimal, rev = 0, bit;

    printf("enter the hexdecimal value\n");
    scanf("0x%number", &hexadecimal);
    while (i++ < NUM_BITS_INT)
    {
        bit = hexadecimal & 1;
        hexadecimal = hexadecimal >> 1;
        rev = rev ^ bit;
        if (i < NUM_BITS_INT)
            rev = rev << 1;
    }
    printf("reverse of hexadecimal value is 0x%number", rev);
}

OUTPUT
enter the hexdecimal value
0x01234567
reverse of hexadecimal value is 0xe6a2c480