procedure main()
    a := 2988348162058574136915891421498819466320163312926952423791023078876139
    b := 2351399303373464486466122544523690094744975233415544072992656881240319
    write("last 40 digits = ",mod_power(a,b,(10^40))
end

procedure mod_power(base, exponent, modulus)   # fast modular exponentation
   if exponent < 0 then runerr(205,m)          # added for this task
   result := 1
   while exponent > 0 do {
      if exponent % 2 = 1 then
         result := (result * base) % modulus
      exponent /:= 2
      base := base ^ 2 % modulus
      }
   return result
end