用指针和数组两种方法实现如下功能：将一个字符串按逆序存放。

#include 
#include 
void dz(char *str);
int main()
{

    char str[100];
    printf("输入一个字符串：");
    scanf("%s",str);
    dz(str);
    printf("倒置后的字符串：%s\n",str);
    return 0;
}
void dz(char *str)
{
    int len;
    char *p0,*p1,c;
    len=strlen(str);
    p0=&str[0];
    p1=&str[len-1];
    while(1)
    {
        c=*p1;
        *p1=*p0;
        *p0=c;
        p0++;p1--;
        if(p1<=p0)
            break;
    }
}

#include
#include
char* inv1(char*s)
{
	int i,n;
	char ch;
	n=(int)strlen(s);
	for(i=0;i<=n/2;i++)
	{
		ch=s[i];
		s[i]=s[n-1-i];
		s[n-1-i]=ch;
	}
	return s;
}
char *inv2(char*s)
{
	char *p1,*p2;
	char ch;
	p1=s;
	p2=s+strlen(s)-1;
	while(p1	{
		ch=*p1;
		*p1=*p2;
		*p2=ch;
		p1++;
		p2--;
	}
	return s;
}
int main()
{
	char str[]="hello!";
	printf("原始字符串为%s\n",str);
	printf("数组逆序后字符串为:\n");
	puts(inv1(str));
	printf("指针逆序后字符串为:\n");
	puts(inv2(str));//两次逆序和原来一样
	return 0;
}

#include 
#include 

char* fun1(char*s)
{
    int i,n;
    char ch;
    n=(int)strlen(s);
    for(i=0;i<=n/2;i++)
    {
        ch=s[i];
        s[i]=s[n-1-i];
        s[n-1-i]=ch;
    }
    return s;
}
char *fun2(char*s)
{
    char *p1,*p2;
    char ch;
    p1=s;
    p2=s+strlen(s)-1;
    while(p1    {
        ch=*p1;
        *p1=*p2;
        *p2=ch;
        p1++;
        p2--;
    }
    return s;
}
int main()
{
    char str[]="1234567890";
	char buf[]="abcdefgh";
    printf("原始字符串为%s\n",str);
    printf("数组逆序后字符串为:\n");
    puts(fun1(str));
	printf("原始字符串为%s\n",buf);
    printf("指针逆序后字符串为:\n");
    puts(fun2(buf));//两次逆序和原来一样
    return 0;
}

原始字符串为1234567890
数组逆序后字符串为:
0987564321
原始字符串为abcdefgh
指针逆序后字符串为:
hgfedcba
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