Write down an unambiguous grammar that generates the set of strings{s;,s;,s;s;s,...}.
时间: 2024-05-30 16:12:53 浏览: 12
Here is a grammar that generates the specified set of strings:
S -> S;S | ε
Explanation:
S represents a set of semicolons and can be expanded to include additional semicolons by recursively applying the production rule S -> S;S. The empty string is also included in the set and is represented by the production rule S -> ε.
相关问题
The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()
() to determine the truth value of an array.
This message is a warning message that is encountered when working with boolean arrays in Python. In Python, boolean arrays can have multiple elements, and determining the truth value of such an array can be ambiguous. To avoid this ambiguity, the warning message suggests using either the a.any() or a.all() functions to determine the truth value of the array.
The a.any() function returns True if any element in the array is True, while the a.all() function returns True only if all elements in the array are True. By using either of these functions, you can ensure that the truth value of the array is unambiguous and can be reliably used in your code.
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