please explain what is this range mean

1≤|Ai|≤10

Can you point out exactly the questions where these constrains are given? The A_i can be interpreted differently depending on the context.

Let assume A is an array, then A_i is the i^{th} element of the array A. So according the the above constrains given, the array elements are guaranteed to be in between 1 and 10 (both included).

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