Определить период

...

How many working days in year 1970?

Here is the detail of the calculation:

Because 1970 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 9 public holidays that do not fall during a weekend and we obtain 252 working days in 1970.

Here is the list of these 9 public holidays:

1. Solenidade da Santa Mãe de Deus : четверг, 1 январь, 1970
2. Sexta-Feira Santa : пятница, 27 март, 1970
3. Dia do Trabalhador : пятница, 1 май, 1970
4. Corpo de Deus : четверг, 28 май, 1970
5. Dia de Portugal : среда, 10 июнь, 1970
6. Implantação da República : понедельник, 5 октябрь, 1970
7. Restauração da Independência : вторник, 1 декабрь, 1970
8. Dia da Imaculada Conceição : вторник, 8 декабрь, 1970
9. Natal : пятница, 25 декабрь, 1970

And here are the 4 public holidays falling on a weekend:

1. Páscoa : воскресенье, 29 март, 1970
2. Dia da Liberdade : суббота, 25 апрель, 1970
3. Assunção de Nossa Senhora : суббота, 15 август, 1970
4. Todos os Santos : воскресенье, 1 ноябрь, 1970