题解 | 计算日期到天数转换

def is_leap_year(year):
    return year % 4 == 0 and (year % 100 != 0 or year % 400 == 0)

def days_in_month(year, month):
    if month == 2:
        return 29 if is_leap_year(year) else 28
    elif month in [1, 3, 5, 7, 8, 10, 12]:
        return 31
    else:
        return 30

def day_of_year(year, month, day):
    days = 0
    for m in range(1, month):
        days += days_in_month(year, m)
    days += day
    return days

# 读取输入
year, month, day = map(int, input().split())

# 计算并输出结果
print(day_of_year(year, month, day))