We prove that Strings-and-Coins -- the combinatorial two-player game generalizing the dual of Dots-and-Boxes -- is strongly PSPACE-complete on multigraphs. This result improves the best previous result, NP-hardness, argued in Winning Ways. Our result also applies to the Nimstring variant, where the winner is determined by normal play; indeed, one step in our reduction is the standard reduction (also from Winning Ways) from Nimstring to Strings-and-Coins.

翻译：我们证明字符串和硬币 -- -- 组合式双玩家游戏 -- -- 概括多盘和双盘的组合式双玩家游戏 -- -- 在多个数字中已明显完成 PSPACE 。 这个结果改进了前一最佳结果, 即NP- 硬性( Winning Woods ) 。 我们的结果也适用于Nimstring 变体, 胜者由普通游戏来决定; 事实上,我们削减的一个步骤就是从Nimstring到字符串和硬性( Strings)的标准削减(也从Winning ways ) 。