| author | Christian Urban <christian.urban@kcl.ac.uk> |
| Mon, 27 Jul 2020 11:02:48 +0100 | |
| changeset 741 | e66bd5c563eb |
| parent 701 | progs/catastrophic.js@681c36b2af27 |
| child 745 | 7dc3643a0cc5 |
| permissions | -rw-r--r-- |
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// A case of catastrophic backtracking in JavaScript/Node.js |
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// |
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// regex: (a*)*b |
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// strings: aa... |
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// |
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// call with: |
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// |
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// $> node catastrophic.js 20 |
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// |
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// call with timing as: |
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// |
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// $> time node catastrophic.js 25 |
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const args = process.argv[2] |
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var str = 'a'.repeat(args); |
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console.log(str) |
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var re = /^((a)*)*b$/; |
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var res = re.test(str); |
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console.log(res) |