19 lines
674 B
Plaintext
19 lines
674 B
Plaintext
No 555
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Note: this task is only for students of "Formal languages and
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complexity theory" taught in English.
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[Your program should read lines from the standard input and check each
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line separately (without end-of-line character). Please use regular
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expressions as much as possible (in particular, try not to use
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logical operators outside the regeular expression). If it is
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possible, use just one regular expression.]
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For each string from the standard input, check whether it is a 9-digit
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phone number (format "NNN-NNN-NNN" or "NNN NNN NNN"), not beginning
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with "555". Write "true"/"false" on the standard output accordingly.
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POINTS: 3
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DEADLINE: 2019-11-21 17:00
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