If a date of May 5 is given, then the first half of April and the second half of April are obtained. If it is May 20, then the first half of May and the second half of April are obtained. What needs to be considered here is the special situation in February
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May 5th, how do you know that it is the first half of April and the second half of April?
May 20th, it is the first half of May and the second half of April?
Where is the dividing point?
Can the questioner give me some advice? Any detailed explanation?