Описание
string
bcpowmod ( string x, string y, string modulus [, int scale] )
Use the fast-exponentiation method to raise x
to the power y with respect to the modulus
modulus. The optional
scale can be used to set the number of
digits after the decimal place in the result.
Замечание:
Because this method uses the modulus operation, non-natural numbers
may give unexpected results. A natural number is any positive
non-zero integer.