字符串逆序

//字符串逆序
/*
	Author :blain
	Data   :2015/08/25
*/
#include <stdio.h>
#include <malloc.h>

//新創建等長度的數組，將原數組從末字符一次放入新數組

char *Reverse_String(char *src)
{
	if(NULL==src)
		return src;
	char *p = src;
	int size = 0;
	while(*++p)
	{
		size++;
	}
	p--;
	char * store=(char*)malloc((size+1)*sizeof(char));
	char * q = store;
	while(p>=src)
	{
		*q++= *p--;
	}
	*q='\0';
	return store;
}

//原地交換字符，使用了第三個變量
char *swap_reverse(char *s)
{
	if(NULL==s)
		return s;
	char *left = s;
	char *right = s;
	char temp = NULL;
	while(*right)
	{
		right++;
	}
	right--;

	while(right>left)
	{
		temp = *right;
		*right-- = *left;
		*left++ = temp;
	}
	return s;
}

//原地交換字符，不使用第三個變量
char *reverse(char *s)
{
	if(NULL==s)
		return s;
	char *left = s;
	char *right = s;
	while(*right)
	{
		right++;
	}
	right--;

	while(right>left)
	{
		 *left =  *left^*right;
		 *right = *left^*right;
		 *left = *left++^*right--;
	}
	return s;
}

void ReversePrint(char *s)
{
	if(*(s+1)!='\0')
		ReversePrint(s+1);
	printf("%c\n",*s);
}

int main(void)
{
	char a[] = "hello";
	//char *dec = Reverse_String(src);
	//printf("%s\n",dec);

	//char *dec1 = swap_reverse(a);
	//printf("%s\n",dec1);

	//char *dec2=reverse(a);
	//printf("%s\n",dec2);
	ReversePrint(a);
	return 0;
}