| author | Christian Urban <christian.urban@kcl.ac.uk> |
| Fri, 26 Sep 2025 23:10:52 +0100 | |
| changeset 990 | 8cb2e171d952 |
| parent 753 | 30ea6b01db46 |
| permissions | -rwxr-xr-x |
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#!/usr/local/bin/node |
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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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// $> ./catastrophic.js 20 |
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// |
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// call with timing as: |
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// |
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// $> time ./catastrophic.js 25 |
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const args = process.argv[2] |
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var str = 'a'.repeat(args); |
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console.log(str) |
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var re = /^((a)*)*b$/; |
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var res = re.test(str); |
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console.log(res) |