# File lib/openid/util.rb, line 191 def Util.powermod(x, n, q) counter=0 n_p=n y_p=1 z_p=x while n_p != 0 if n_p[0]==1 y_p=(y_p*z_p) % q end n_p = n_p >> 1 z_p = (z_p * z_p) % q counter += 1 end return y_p end