746.输出字符串

#include<stdio.h>
#include<string.h>
int main()
{
    char a[101]="",b[102]="";
    int i=0;
    gets(a);
    while(a[i]>0){
        if(a[i+1]==0){
        b[i]=a[i]+a[0];}    
        else {b[i]=a[i]+a[i+1];}
        i++;
    }
    puts(b);
    return 0;
}