Two Way algorithm


Definition: Partition ("factor") the pattern, x, into left, xl, and right, xr, parts in such a way to optimize searching. Compare xr left to right then, if it matches, compare xl right to left.

Generalization (I am a kind of ...)
string matching algorithm.

See also Knuth-Morris-Pratt algorithm, Boyer-Moore.

Note: It "can be viewed as an intermediate between the classical algorithms of Knuth, Morris, and Pratt on the one hand and Boyer and Moore, on the other hand."

Author: PEB


Christian Charras' and Thierry Lecroq's Exact String Matching Algorithms (C)

More information

Maxime Crochemore and Dominique Perrin, Two-way string-matching, Journal of the ACM, 38(3):651-675, July 1991.

Go to the Dictionary of Algorithms and Data Structures home page.

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Entry modified 24 August 2017.
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Cite this as:
Paul E. Black, "Two Way algorithm", in Dictionary of Algorithms and Data Structures [online], Vreda Pieterse and Paul E. Black, eds. 24 August 2017. (accessed TODAY) Available from: