请教一下大佬们，第9个检查点报错，为什么啊？孩子真的看不出来哪里错了(>_<)

###P5707###

s, v = map(int, input().split())
time = s / v                        #单位为分钟
time += 10
if time % 1:
    pass
else:
    time = int(time) + 1

if time <= 60:
    minute = int(60 - time)
    hour = int(7)
    print(f"{hour:02d}:{minute:02d}")
elif 60 < time <= 480:
    hour_need = time // 60
    minute_need = time % 60
    hour = int(7 - hour_need)
    minute = int(60 - minute_need)
    print(f"{hour:02d}:{minute:02d}")
else:                               #出发时间为前一天的情况
    time = time - 480
    hour_need = time // 60
    minute_need = time % 60
    hour = int(23- hour_need)
    minute = int(60 - minute_need)
    print(f"{hour:02d}:{minute:02d}")