A77 is to sort all people;

Then divide it by A33. Because there is another requirement, girls are arranged in high and low order, so there is actually only one arrangement for girls, so divide it by the number of girls who are freely arranged: A33.

(2)A77 is to sort all people;

Then divide it by A33. Because there is another requirement, girls are arranged in a certain row, so there is actually only one arrangement for girls, so divide it by the number of types that girls can arrange freely: A33.

In the same way, dividing by A44 is to consider boys ~

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