ARITHMETIC OPERATION METHOD AND ARITHMETIC OPERATION DEVICE

In an arithmetic operation method and an arithmetic operation device arithmetic operations such as exponentiation or scalar multiplication can be performed at high speed. In the case where there exists a plurality of different elements Y and each element Y is represented by tuples in which a plurality of different elements X are combined with an operator, an arithmetic operation method for calculating each element Y by using an electronic computer, associates each element Y with the element X by setting each element X, sets temporary data having an index indicating whether or not each element Y has an identical element X for each element X, and represents each element Y by the temporary data combined with the operator. When there is a combination of temporary data which is common in plurality of elements Y in temporary data contained in each element Y, new temporary data is set by combining the common temporary data and each element Y consisting of each tuple is calculated using the new temporary data.