How to solve a problem in computer science?

Question

Python

You have to write out from the calendar the days of a certain month of a non-leap year, which fall on Sundays.
First, a number is entered (from 1 to 7), on which the first Sunday of January falls and the number of the month in which you need to select all Sundays,
explain at least in which direction to think

Answer 1

Days in a year continuous sequence 1-365. It's not a leap year, so February has 28 days.
Every month is an interval. January - from 1 to 31, February - from 32 to (31+28)...
1) First, enter the number (from 1 to 7) that falls on the first Sunday of January
This is the initial offset idx
2) Go by 7 from the initial offset (inclusive - January was suddenly set) idx = idx + 7.
3) If we fall into the interval of a given month, then subtract the beginning of the interval and get the date.
ps. In all formulas, you need to play around with + -1
, this is a head-on solution without libraries, there are options and faster.