定义一个时期

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How many working days in year 1965?

Here is the detail of the calculation:

Because 1965 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 3 public holidays that do not fall during a weekend and we obtain 258 working days in 1965.

Here is the list of these 3 public holidays:

1. New Year's Day : 1965年1月1日星期五
2. Good Friday : 1965年4月16日星期五
3. National Day : 1965年8月9日星期一

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

1. Labour Day : 1965年5月1日星期六
2. Christmas Day : 1965年12月25日星期六