1277 How Many Days Are There - How many days match given weekday and date criteria

Sep 17, 2026

Problem-solving task for a special extended Gregorian-style calendar spanning from 2000000 years B.C. to 2000000 years A.D. The calendar defines leap years, weekday recurrence starting from Monday on Jan 1, year 1 A.D., and standard month lengths with February adjusted for leap years. Each dataset asks for the count of days between a given start date and end date (inclusive) whose weekday equals a required value and whose day-of-month equals a required number. Input ends when m=0 and n=0; output requires one integer per dataset with no extra spaces.

LanguageEnglish

CategoryExam

FormatPDF

Pages2

Reading Time5 min

AccessFree to download

Input

Data set format

Output

Matching days count

Calendar rules

Leap years and month lengths

Weekday recurrence

Constraints

1277 How Many Days Are There \Unfortunately, I can not attend the party in the 10th this month," a friend said to me, \ You know, only Thursday is my holiday. Although I'm longing for the party, I'm sorry that I will not be present then." \It doesn't matter. I hope that you will be present the next time." ...... Have you ever encounter the situation like that? No matter how regretful you feel about it, still you could do nothing. So, we desire to 􀀌nd a way to know in a period how manys days of which not only the date but the day of week conform to our demand there are. In this problem, we assume that we use a special calendar from ancient to modern times. In the calendar, we stipulate as follows: 0. In the calendar, there isn't year 0, and we use 1 year B.C. instead. And also we assume that 1 year B.C. is a leap year. In this problem, 0 means 1 year B.C. and-1 means 2 years B.C. , ..., and so on. 1. In the calendar, Jan. 1st, 1 year A.D. is Monday, the following days are Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday in proper order. And then from Monday to Sunday to keep on recurring. 2. If a certain year is divisible by 4 and not divisible by 100, then it's a leap year. But if it is divisible by 400, it's a leap year too. 3. In a year there are 12 months. In January, March, May, July, August, October and December there are 31 days each. In April, June, September, November there are 30 days each. And in February, if the year is a leap year, there are 29 days, otherwise there are 28 days. 4. Your program should deal with the date from 2000000 [year B.C. to](year B.C. to) 2000000 A.D.. Input The input 􀀌le for this problem will contains a series of data sets. Each data set will begin with two integers. The 􀀌rst integer m (0 􀀔 m 􀀔 6) is the day of week in demand. If m = 0 represents the day of week is Sunday, and then m = 1 represents Monday, m = 2 represents Thuesday, . . . , m = 6 represents Saturday. The second integer n (0 􀀔 n 􀀔 31) is the day part of the date in demand. The end of input is signi􀀌ed by the data set with m = 0 and n = 0 . And this data set should not be processed. If the data set doesn't indicate the end of the input, there will be 6 integers y 1 , m 1 , d 1 , y2 , m2 , d2 , represent the start date and the end date. And you should process between the start date and the end date. Among these integers, y 1 , m 1 , d 1 are the year part, the month part, the day part of the start date, and y2 , m2 , d2 are the year part, the month part, the day part of the end date. You may assume that the start date and the end date conform to the calendar. The end date will not be earlier than the start date. Output The output for each data set should include a line contains a integer which tells from the start date to the end date ( including the start date and the end date ) how many days conform to our demands. That is, if the day of week of a special date equals to m and the day part of this date equals to n, we say the date conform to our demands. You should not print any more whitespaces or blank lines in the output. Sample Input 0 28 1999 11 18 1999 11 28 5 28 1999 11 18 1999 11 28 5 13 1999 1 1 1999 12 31 0 30 1976 6 30 1999 11 28 0 0 Sample Output 1 0 1 35

FAQs

What calendar rules are used to determine weekdays and dates?

The rules specify no year 0, use 1 year B.C. as year 0, assume that year is a leap year, set Jan 1 of year 1 A.D. as Monday, and follow standard leap-year logic plus month day counts with February adjusted.

How does the input end and how are datasets structured?

Each dataset starts with two integers m (weekday demand) and n (day-of-month demand). The input ends at m=0 and n=0; otherwise, six more integers y1, m1, d1, y2, m2, d2 define the start and end dates.

What exactly should the program output for each dataset?

For each dataset, output a single integer equal to the number of inclusive dates between the start and end date whose weekday equals m and whose day part equals n.

Sep 17, 2026

Uploaded by Jordan Avery