字节内高低位互换

[kuaipian4724]

如题，AE007845转换为EA008754，C++如何实现

[wang0635]

#include<stdio.h>

unsigned int myswap(unsigned int x);

int main()
{
    unsigned int	a = 0xAE007845, b;
    b = myswap(a);
    printf("a=%x, b=%x\n", a, b);
    return 0;
}

unsigned int myswap(unsigned int x)
{
	int		i, size = sizeof(x);
	unsigned int	result;
	char	*px = (char *)&x, *pr = (char *)&result;
	for (i = 0; i < size; i++)
		pr[i] = (px[i] & 0x0f) << 4 | (px[i] & 0xf0) >> 4;
	return result;
}

[自信男孩]

#include <iostream>
#include <cstdio>
#include <cstring>

using namespace std;

int main()
{
    unsigned int    a = 0xAE007845, b, i;

    char buf[16], ch;
    snprintf(buf, sizeof(buf), "%X", a);

    for (i = 0; i < strlen(buf) - 1; i += 2) {
        ch = buf[i];
        buf[i] = buf[i+1];
        buf[i+1] = ch;
    }

    cout<<buf<<endl;
    sscanf(buf, "%X", &b);

    printf("%X --> %X\n", a, b);
    cout<<a<<b<<endl;

    return 0;
}

作为一个参考吧 方法可能多种，具体用哪种要根据实际使用场景。

[日立奔腾浪潮微软松下联想]

#define HALFBYTE_SWAP(x) (((unsigned int)(x) >> 4) & 0x0f0f0f0f | ((x) << 4) & 0xf0f0f0f0)