METHOD AND DEVICE FOR BIDDING TWO OR MORE KINDS OF WEALTH AND ITS PROGRAM

摘要

PROBLEM TO BE SOLVED: To make secret the combined bidding of two or more kinds of wealth other than bidding information even to the other bidders and bid opening persons.;SOLUTION: A price is expressed with vectors with E(1) and E(z) encrypted by a semi-uniform type E as components based on a number 1 and the other numbers z, and bidders x add E(z) corresponding to a bidding price b_x to E₀ and E_x among null function encrypted sentences E_0' to E_b whose number is larger than that of the number b of the bidders by one, and those respective bidders x carry out this processing in a preliminarily decided order. After this processing has been carried out by all the bidders x, the maximum value m in the components of E₀ is calculated, and the combination of wealth which is turned to be z at first by decoding the m-th components of E₀ is defined as optimal assignment A^*, and the assignment number is defined as Q, and the component number which is turned to be z at first by decoding the Q-th components of those respective E_x is defined as a payment sum p_x.;COPYRIGHT: (C)2004,JPO&NCIPI