Определить период

...

How many working days in year 1987?

Here is the detail of the calculation:

Because 1987 is not a leap year, it has 365 days.

Let's remove 52 saturdays and 52 sundays. It remains 261 days.

Now, let's remove 7 public holidays that do not fall during a weekend and we obtain 254 working days in 1987.

Here is the list of these 7 public holidays:

1. New Year's Day : четверг, 1 январь, 1987
2. Good Friday : пятница, 17 апрель, 1987
3. Easter Monday : понедельник, 20 апрель, 1987
4. Labour Day : пятница, 1 май, 1987
5. Establishment Day : среда, 1 июль, 1987
6. National Day : четверг, 1 октябрь, 1987
7. Christmas Day : пятница, 25 декабрь, 1987

And here are the 2 public holidays falling on a weekend:

1. Holy Saturday : суббота, 18 апрель, 1987
2. Boxing Day : суббота, 26 декабрь, 1987