常用代码

• 二进制字符串转十进制数字
• 内存高低位互换

二进制字符串转十进制数字

// 二进制字符串转
unsigned long fun(char* s, int len)
{
    unsigned long i,sum=0;
    for(i=0;s[i]!='\0'&&i<len;i++)
        sum=2*sum+(s[i]-48);       //这里的48等价于'0'
    return sum;
}

内存高低位互换

// 高低位互换
void HighAndLowPositionExchange(char* src, size_t len)
{

	unsigned int maxIndex = len / 2;

	for (size_t i = 0; i < maxIndex; i++) {

		src[i] += src[i+2] ;

		src[i+2] = src[i] - src[i+2];

		src[i] = src[i] - src[i+2];
	}
}