int main(int argc, char** argv) {
	int s;		//s means distance.
	int v;		//v means distance per minute.
	int time;
	scanf("%d%d",&s,&v);
	//Use Time.
	if (v == 0) {
		time = 0;
	}
	if (s % v == 0) {
		time = s / v;
	}
	else {
		time = s / v + 1;
	}
	time = time + 9;
	//Do Rubbish Items.
	int hour = 7;
	int minute = 59;
	while (time != 0) {
		if (minute == 0) {
			if (hour != 0) {
				hour--;
				minute = 59;
			}
			if (hour == 0) {
				hour = 23;
				minute = 59;
			}
		} else {
			minute--;
		}
		time--;
	}
	//根据条件输出，如果小时或者是分钟数小于10，在前面补0.
	if (hour < 10 && minute >= 10) {
		printf("0%d:%d",hour,minute);
	} 
	if (hour < 10 && minute < 10) {
		printf("0%d:0%d",hour,minute);
	}
	if (hour >= 10 && minute < 10) {
		printf("%d:0%d",hour,minute);
	}
	if (hour >= 10 && minute >= 10) {
		printf("%d:%d",hour,minute);
	}
}

只能通过前6个测试用例，之后的测试用例无法通过。求大佬帮忙看看，多谢！