#include<stdlib.h>

 #include <stdio.h>

 #include <time.h>

 #include <windows.h>

 int main()

 {

     int i;

 #if 1

     int bootdelay = ;

     printf("Hit any key to stop autoboot: %2ds ", bootdelay);    //"%2ds " 2byte数字 1字节's' 1字节空格

     fflush(stdout);

     while(bootdelay > )

     {

         Sleep();

         --bootdelay;

         printf("\b\b\b\b%2ds ", bootdelay);    //因格式占4byte，2byte数字、1字节‘s’、1字节空格，所以需要4个'\b' backspace 退格非删除

         fflush(stdout);

     }

 #endif

     printf("\n");

     printf(".................\n");

     for(i = ; i > -; i--)

     {

         if(i == )

         {

             printf("Wait %ds", i);

             fflush(stdout);

             Sleep();

         }

         else

         {

             printf("\b\b%ds", i);

             fflush(stdout);

             Sleep();

         }

     }

     printf("\n");    

     return ;

 }