倒计时小程序

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char *argv[])
{
	int i;
	int num = 0;
	char c_num;

	printf("please enter a countdown number[1-9]:");
	
	c_num = getchar();
	getchar();

	num = atoi((const char *)&c_num);
	
	printf("COUNTDOWN:\n");
	for(i = num; i > 0; i--)
	{
		printf("\b\b");
		printf("%2d",i);
		fflush(stdout); /*write buffer to the screen(stdout), if needed*/

		sleep(1);
	}
	printf("\n");
	
	return 0;
}