{-# LANGUAGE BangPatterns #-}

import           Control.Monad.Fix
import           Control.Monad.ST
import           Data.Bool
import qualified GHC.Integer.GMP.Internals   as GMP
import qualified Data.Vector.Unboxed         as VU
import qualified Data.Vector.Unboxed.Mutable as VUM

main :: IO ()
main = do
  [a, b, n] <- map read . words <$> getLine
  print $ tetration a b n

tetration :: Int -> Int -> Int -> Int
tetration a b m
  | m == 1 = 0
  | a == 0 = bool 0 1 (even b)
  | b == 0 = 1
  | b == 1 = a `mod` m
  | b == 2 = powModInt (a `mod` m) a m
  | otherwise = powModInt (a `mod` m) (prev + phi) m
  where
    !phi = eulerPhi m
    prev = tetration a (b - 1) phi
    powModInt :: Int -> Int -> Int -> Int
    powModInt a b c = fromInteger $ GMP.powModInteger (fromIntegral a) (fromIntegral b) (fromIntegral c)
    {-# INLINE powModInt #-}

eulerPhi :: Int -> Int
eulerPhi n = runST $ do
  xs <- VU.unsafeThaw $ VU.fromList [n, n, 2]
  ys <- loopFor xs
  p  <- VUM.unsafeRead ys 0
  q  <- VUM.unsafeRead ys 1
  if q > 1 then return (p - p `div` q) else return p
    where
      loopFor :: VUM.STVector s Int -> ST s (VUM.STVector s Int)
      loopFor xx = do
        idx <- VUM.unsafeRead xx 2
        if idx * idx > n then return xx else do
          xret <- VUM.unsafeRead xx 0
          xn   <- VUM.unsafeRead xx 1
          if xn `mod` idx /= 0
            then do
              VUM.unsafeWrite xx 2 (idx + 1)
              loopFor xx
            else do
              VUM.unsafeWrite xx 0 (xret - xret `div` idx)
              whileXS <- loopWhile xx
              VUM.unsafeWrite whileXS 2 (idx + 1)
              loopFor whileXS
                where
                  loopWhile :: VUM.STVector s Int -> ST s (VUM.STVector s Int)
                  loopWhile ks = do
                    whileN <- VUM.unsafeRead ks 1
                    whileI <- VUM.unsafeRead ks 2
                    if whileN `mod` whileI /= 0 then return ks else do
                      VUM.unsafeWrite ks 1 (whileN `div` whileI)
                      loopWhile ks