Define a period

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How many working days in year 2012?

Here is the detail of the calculation:

Because 2012 is a leap year, it has 366 days.

Let's remove 52 saturdays and 53 sundays. It remains 261 days.

Now, let's remove 11 public holidays that do not fall during a weekend and we obtain 250 working days in 2012.

Here is the list of these 11 public holidays:

1. Seollal / Korean New Year Holiday : Monday, 23 January, 2012
2. Seollal / Korean New Year Holiday : Tuesday, 24 January, 2012
3. 삼일절 : Thursday, 1 March, 2012
4. 어린이날 : Monday, 7 May, 2012
5. 석가탄신일 : Monday, 28 May, 2012
6. 현충일 : Wednesday, 6 June, 2012
7. 광복절 : Wednesday, 15 August, 2012
8. 추석 : Monday, 1 October, 2012
9. 개천절 : Wednesday, 3 October, 2012
10. 한글날 : Tuesday, 9 October, 2012
11. 성탄절 : Tuesday, 25 December, 2012

And here are the 6 public holidays falling on a weekend:

1. 신정 : Sunday, 1 January, 2012
2. Seollal / Korean New Year Holiday : Sunday, 22 January, 2012
3. 석가탄신일 : Saturday, 28 April, 2012
4. 어린이날 : Saturday, 5 May, 2012
5. 추석 : Saturday, 29 September, 2012
6. 추석 : Sunday, 30 September, 2012