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arXiv · 2101.09699

Longest segment of balanced parentheses -- an exercise in program inversion in a segment problem (Functional Pearl)

Shin-Cheng Mu·Tsung-Ju Chiang
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Abstract

Given a string of parentheses, the task is to find the longest consecutive segment that is balanced, in linear time. We find this problem interesting because it involves a combination of techniques: the usual approach for solving segment problems, and a theorem for constructing the inverse of a function -- through which we derive an instance of shift-reduce parsing.

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Shin-Cheng Mu, Tsung-Ju Chiang. 2021-01-24. Longest segment of balanced parentheses -- an exercise in program inversion in a segment problem (Functional Pearl). https://doi.org/10.1017/s0956796821000253

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