MPMD on Two Sources with Lookahead
摘要
The min-cost perfect matching with delays problem on two sources (2-MPMD) captures the critical trade-off between match and wait, and has been extensively studied recently. A 3-competitive deterministic algorithm and a 2-competitive randomized algorithm were proposed, where 2 is also the lower bound. In this paper, we consider a variation where an algorithm is allowed to look ahead for certain time, exploring the power of future knowledge in online decisions. We devise a \(\frac{3+\tau }{1+\tau }\) -competitive deterministic algorithm and a randomized algorithm which is \(\left( 2-(2\sqrt{2}-2)\tau \right) \) -competitive when \(\tau \le \frac{1}{2}\) and \(\left( 2 + 2\tau -\sqrt{4\tau ^2 + 4\tau - 1}\right) \) -competitive otherwise, where \(\tau \) is the length of the foreseen time period.