完全相同的两年

codeforces    B. The Same Calendar

The girl Taylor has a beautiful calendar for the year y. In the calendar all days are given with their days of week: Monday, Tuesday, Wednesday, Thursday, Friday, Saturday and Sunday.

The calendar is so beautiful that she wants to know what is the next year after y when the calendar will be exactly the same. Help Taylor to find that year.

Note that leap years has 366 days. The year is leap if it is divisible by 400 or it is divisible by 4, but not by 100 (https://en.wikipedia.org/wiki/Leap_year).

Input

The only line contains integer y (1000 ≤ y < 100'000) — the year of the calendar.

Output

Print the only integer y' — the next year after y when the calendar will be the same. Note that you should find the first year after y with the same calendar.

 

Examples

　　input

　　2016

　　output

　　2044

　　input

　　2000

　　output

　　2028

 

　　input

　　50501

　　output

　　50507

小析：求解出与给出年份完全相同的下一年，不仅需要平闰相同，还需要星期相同

 1 def is_leap(year):
 2     if (year % 400 == 0 or year % 4 == 0 and year % 100 != 0):
 3         return 1
 4     else:
 5         return 0
 6 
 7 
 8 if __name__ == '__main__':
 9     year = 0
10     try:
11         year = int(input())
12     except:
13         exit(0)
14     sum = 0
15     next_year = year + 1
16     while True:
17         if is_leap(next_year) == 0:
18             sum += 1
19         else:
20             sum += 2
21         if (sum % 7 == 0) and (is_leap(year) == is_leap(next_year)):
22             print(next_year)
23             break
24         else:
25             next_year += 1

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