First of all, you must have data, right? For example, it contains business data (staple food, dishes, etc.), then it may be a dictionary. The staple food in the dictionary is an array, right, and the dishes are also arrays, right? Suppose you have three sections now, then don’t you have three arrays, staple food, dishes, and others? How many rows are there in the staple food, that is, how many data are there in the array of your staple food, right? You should understand it this way.
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First of all, you must have data, right? For example, it contains business data (staple food, dishes, etc.), then it may be a dictionary. The staple food in the dictionary is an array, right, and the dishes are also arrays, right?
Suppose you have three sections now, then don’t you have three arrays, staple food, dishes, and others? How many rows are there in the staple food, that is, how many data are there in the array of your staple food, right?
You should understand it this way.