It means integers from 1 through m_0, inclusive. I.e., 0 is not included but m_0 is. For example, (1,4) means either 2 or 3, whereas [1,4] means any of 1, 2, 3, or 4.

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Please explain the notation "(0,m_0]" for the range from which
random numbers are selected by "rand".
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