#include <stdio.h>
#include <time.h>

time_t  get_caltime(char *tstr);

main()
{
	time_t  cal_time, now_time, inter, prev;
	char    buff[100];
	int	day, hour, min, sec;
	struct tm
		*tm_now;

	printf("YYYYMMDDHHMMSS : ");
	scanf("%s", buff);
	cal_time = get_caltime(buff);
	if(cal_time == -1){
		printf("変換失敗\n");
		return;
	}
	now_time = time(NULL);
	if(cal_time <= now_time){
		printf("入力した日時が不適切です.\n");
		return;
	}

	printf("\033[2J");
	tm_now = localtime(&cal_time);
	printf("%4d年%2d月%2d日 %2d時%2d分%2d秒まで\n",
		tm_now->tm_year+1900, tm_now->tm_mon+1, tm_now->tm_mday,
		tm_now->tm_hour, tm_now->tm_min, tm_now->tm_sec);

	prev = -1;
	for(;;){
		now_time = time(NULL);
		if(prev == now_time)
			continue;
		prev = now_time;
		inter = cal_time - now_time;
		if(inter < 0)
			break;
		sec = inter % 60;
		inter /= 60;
		min = inter % 60;
		inter /= 60;
		hour = inter % 24;
		day = inter / 24;
		printf("あと%d日と%2d時間%2d分%2d秒\n", day, hour, min, sec);       
	}
}


time_t  get_caltime(char *tstr)
{
	char    buf[20];
	time_t  cal_time;
	struct tm
		work_tm;

	if(strlen(tstr) != 14)
		return(-1);
	strncpy(buf, tstr, 4);
	buf[4] = '\0';
	work_tm.tm_year = atoi(buf) - 1900;
	strncpy(buf, tstr+4, 2);
	buf[2] = '\0';
	work_tm.tm_mon = atoi(buf) - 1;
	strncpy(buf, tstr+4+2, 2);
	work_tm.tm_mday = atoi(buf);
	strncpy(buf, tstr+4+2+2, 2);
	work_tm.tm_hour = atoi(buf);
	strncpy(buf, tstr+4+2+2+2, 2);
	work_tm.tm_min = atoi(buf);
	strncpy(buf, tstr+4+2+2+2+2, 2);
	work_tm.tm_sec = atoi(buf);
	work_tm.tm_isdst = -1;
	if((cal_time = mktime(&work_tm)) == -1){
		return(-1);
	}
	return(cal_time);
}

#include <stdio.h>
#include <time.h>

time_t  get_caltime(char *tstr);

main()
{
	time_t  cal_time, now_time, inter, prev;
	char    buff[100];
	int	day, hour, min, sec;
	struct tm
		*tm_now;

	printf("YYYYMMDDHHMMSS : ");
	scanf("%s", buff);
	cal_time = get_caltime(buff);
	if(cal_time == -1){
		printf("変換失敗\n");
		return;
	}
	now_time = time(NULL);
	if(cal_time <= now_time){
		printf("入力した日時が不適切です.\n");
		return;
	}

	printf("\033[2J");
	tm_now = localtime(&cal_time);
	printf("\033[10;25H");
	printf("%4d年%2d月%2d日 %2d時%2d分%2d秒まで\n",
		tm_now->tm_year+1900, tm_now->tm_mon+1, tm_now->tm_mday,
		tm_now->tm_hour, tm_now->tm_min, tm_now->tm_sec);

	prev = -1;
	for(;;){
		if(kbhit()){
			if(getch() == 0x1B)
				break;
		}
		now_time = time(NULL);
		if(prev == now_time)
			continue;
		prev = now_time;
		inter = cal_time - now_time;
		if(inter < 0)
			break;
		sec = inter % 60;
		inter /= 60;
		min = inter % 60;
		inter /= 60;
		hour = inter % 24;
		day = inter / 24;
		printf("\033[11;25H");
		printf("あと%d日と%2d時間%2d分%2d秒", day, hour, min, sec);        
		printf("\033[0K");
	}
}


time_t  get_caltime(char *tstr)
{
	char    buf[20];
	time_t  cal_time;
	struct tm
		work_tm;

	if(strlen(tstr) != 14)
		return(-1);
	strncpy(buf, tstr, 4);
	buf[4] = '\0';
	work_tm.tm_year = atoi(buf) - 1900;
	strncpy(buf, tstr+4, 2);
	buf[2] = '\0';
	work_tm.tm_mon = atoi(buf) - 1;
	strncpy(buf, tstr+4+2, 2);
	work_tm.tm_mday = atoi(buf);
	strncpy(buf, tstr+4+2+2, 2);
	work_tm.tm_hour = atoi(buf);
	strncpy(buf, tstr+4+2+2+2, 2);
	work_tm.tm_min = atoi(buf);
	strncpy(buf, tstr+4+2+2+2+2, 2);
	work_tm.tm_sec = atoi(buf);
	work_tm.tm_isdst = -1;
	if((cal_time = mktime(&work_tm)) == -1){
		return(-1);
	}
	return(cal_time);
}