写一个递归算法，实现字符串逆序存储，要求不另设串存储空间

#include "stdio.h"
#include "string.h"
void main()
{
char str[50]="ABCDEFGHsdfwefsdf123",tmp;
int i,len;
len=strlen(str);
printf("old %s\n",str);
for(i=0;i {
tmp=str[i];
str[i]=str[len-i-1];
str[len-i-1]=tmp;
}
printf("new %s\n",str);
}

#include
using namespace std;
char *Change(char *str){
for(int i=0,j=strlen(str)-1;i {
str[i]+=str[j];
str[j]=str[i]-str[j];
str[i]=str[i]-str[j];
}
return str;
}
int main(){
char *pcStr = new char[15];
strcpy(pcStr, "I am yuchifang");
cout<<"before reverse:"< cout< pcStr=Change(pcStr); // 字符串倒序
cout<<"after reverse"< cout< delete [] pcStr;
while(1);
return 0;
}