代碼文本:
#include "stdio.h"
int main(int argc,char *argv[]){
char s[21],i,j;
printf("Please enter a string length is not more than 10...\n");
scanf("%10s",s);
printf("Before:\n%s\nAfter:\n",s);
for(i=0;s[i];i++);//計算輸入字符串的長度
for(s[j=i--<<1]='\0',j--;i>=0;i--,j-=2){
s[j]=s[j-1]=s[i];
printf("%c%c",s[j],s[j-1]);
}
putchar('\n');
return 0;
}