Simplified and Space-Optimal Semi-Streaming (2+epsilon)-Approximate Matching

Authors Mohsen Ghaffari, David Wajc

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Mohsen Ghaffari
David Wajc

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Mohsen Ghaffari and David Wajc. Simplified and Space-Optimal Semi-Streaming (2+epsilon)-Approximate Matching. In 2nd Symposium on Simplicity in Algorithms (SOSA 2019). Open Access Series in Informatics (OASIcs), Volume 69, pp. 13:1-13:8, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2019)


In a recent breakthrough, Paz and Schwartzman (SODA'17) presented a single-pass (2+epsilon)-approximation algorithm for the maximum weight matching problem in the semi-streaming model. Their algorithm uses O(n log^2 n) bits of space, for any constant epsilon>0. We present a simplified and more intuitive primal-dual analysis, for essentially the same algorithm, which also improves the space complexity to the optimal bound of O(n log n) bits - this is optimal as the output matching requires Omega(n log n) bits.
  • Streaming
  • Semi-Streaming
  • Space-Optimal
  • Matching


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