Research in the area of secure multi-party computation with an unconventional method of using a physical deck of playing cards began in 1989 when den Boer proposed a protocol to compute the logical AND function using five cards. Since then, the area has gained interest from many researchers and several card-based protocols to compute various functions have been developed. In this paper, we propose a card-based protocol called the overwriting protocol that can securely compute the $k$-candidate $n$-variable equality function $f: \{0,1,\ldots ,k-1\}^n \rightarrow \{0,1\}$. We also apply the technique used in this protocol to compute other similar functions.

翻译：使用物理扑克牌进行安全多方计算的非传统方法研究始于1989年，当时den Boer提出了使用五张牌计算逻辑AND函数的协议。此后，该领域引起了许多研究者的兴趣，并开发了多种基于卡牌的计算不同函数的协议。本文提出了一种称为重写协议的卡牌协议，能够安全计算$k$候选$n$变量相等性函数$f: \{0,1,\ldots ,k-1\}^n \rightarrow \{0,1\}$。我们还将该协议中使用的技术应用于计算其他类似函数。