{-# LANGUAGE BangPatterns #-} {-# LANGUAGE MagicHash #-} {-# LANGUAGE UnboxedTuples #-} {- base -} import Control.Arrow import Data.Bits import Data.Char import Data.List (foldl1') import Data.Word import GHC.Exts import Unsafe.Coerce {- bytestring -} import qualified Data.ByteString.Char8 as BSC8 {- integer-gmp -} import qualified GHC.Integer.GMP.Internals as GMP {- vector -} import qualified Data.Vector as V import qualified Data.Vector.Fusion.Stream.Monadic as VFSM import qualified Data.Vector.Unboxed as VU main :: IO () main = do query <- parse1 rep query $ \_ -> do print . solver =<< parse2 solver :: (Int, Int) -> Int solver (n, m) | m == 1 = 0 | n >= m = 0 | n <= 1 = 1 | m <= 200000 = flip mod m $ foldl1' (\acc x -> mod (acc * (mod x m)) m) [1..n] | isPrime m = if n + 1 < m - 1 then flip mod m $ (m - 1) * recipModInt (foldl1' (\acc x -> flip mod m $ acc * (mod x m)) [n + 1 .. m - 1]) m else if n == m - 1 then n else 1 | otherwise = if n >= (m .>>. 1) then 0 else flip mod m $ foldl1' (\acc x -> mod (acc * (mod x m)) m) [1..n] ------------------------------------------------------------------------------- type Parser a = BSC8.ByteString -> Maybe (a, BSC8.ByteString) parseInt :: Parser Int parseInt = fmap (second BSC8.tail) . BSC8.readInt parseChar :: [Char] -> VU.Vector Char parseChar = VU.fromList parse1 :: IO Int parse1 = readLn parse2 :: IO (Int, Int) parse2 = (\vec -> (vec VU.! 0, vec VU.! 1)) . VU.unfoldrN 2 parseInt <$> BSC8.getLine parse3 :: IO (Int, Int, Int) parse3 = (\vec -> (vec VU.! 0, vec VU.! 1, vec VU.! 2)) . VU.unfoldrN 3 parseInt <$> BSC8.getLine parse4 :: IO (Int, Int, Int, Int) parse4 = (\vec -> (vec VU.! 0, vec VU.! 1, vec VU.! 2, vec VU.! 3)) . VU.unfoldrN 4 parseInt <$> BSC8.getLine parseM :: Int -> IO (VU.Vector Int) parseM m = VU.unfoldrN m parseInt <$> BSC8.getLine parseN :: Int -> IO (VU.Vector Int) parseN n = VU.replicateM n parse1 parseNM :: Int -> Int -> IO (V.Vector (VU.Vector Int)) parseNM n m = V.replicateM n $ VU.unfoldrN m parseInt <$> BSC8.getLine parseANBN :: Int -> IO (VU.Vector Int, VU.Vector Int) parseANBN n = do vectup <- VU.replicateM n $ (\vec -> (vec VU.! 0, vec VU.! 1)) . VU.unfoldr (BSC8.readInt . BSC8.dropWhile isSpace) <$> BSC8.getLine return $ VU.unzip vectup parseANBNCN :: Int -> IO (VU.Vector Int, VU.Vector Int, VU.Vector Int) parseANBNCN n = do vectup <- VU.replicateM n $ (\vec -> (vec VU.! 0, vec VU.! 1, vec VU.! 2)) . VU.unfoldr (BSC8.readInt . BSC8.dropWhile isSpace) <$> BSC8.getLine return $ VU.unzip3 vectup ------------------------------------------------------------------------------- infixl 8 .>>., .<<., .>>>. infixl 6 .^. (.^.) :: Bits i => i -> i -> i (.^.) = xor (.>>.) :: Bits i => i -> Int -> i (.>>.) = unsafeShiftR {-# INLINE (.>>.) #-} (.<<.) :: Bits i => i -> Int -> i (.<<.) = unsafeShiftL {-# INLINE (.<<.) #-} (.>>>.) :: Int -> Int -> Int (.>>>.) (I# x#) (I# i#) = I# (uncheckedIShiftRL# x# i#) {-# INLINE (.>>>.) #-} fi :: Int -> Integer fi = fromIntegral {-# INLINE fi #-} fI :: Integer -> Int fI = fromInteger {-# INLINE fI #-} floorSqrt :: Int -> Int floorSqrt = floor . sqrt . fromIntegral {-# INLINE floorSqrt #-} floorLog2 :: Int -> Int floorLog2 x = fromIntegral $ unsafeShiftR y 52 - 1023 where y :: Word64 y = unsafeCoerce (fromIntegral x :: Double) {-# INLINE floorLog2 #-} powModInt :: Int -> Int -> Int -> Int powModInt a b c = fI $ GMP.powModInteger (fi a) (fi b) (fi c) {-# INLINE powModInt #-} recipModInt :: Int -> Int -> Int recipModInt a m = fI $ GMP.recipModInteger (fi a) (fi m) {-# INLINE recipModInt #-} gcdext :: Int -> Int -> (Int, Int, Int) -- a * x + b * y = d => (x, y, d) (d = gcd a b) gcdext a b = (x, y, d) where d = gcd a b (x, y) = case GMP.gcdExtInteger (fi a) (fi b) of (# p, q #) -> (fI p, fI q) {-# INLINE gcdext #-} modInv :: Int -> Int -> Int modInv a mo | 1 == g = mkPos i | otherwise = -1 where (i, _, g) = gcdext a mo mkPos x | x < 0 = x + mo | otherwise = x {-# INLINE modInv #-} stream :: Monad m => Int -> Int -> VFSM.Stream m Int stream !l !r = VFSM.Stream step l where step x | x < r = return $ VFSM.Yield x (x + 1) | otherwise = return $ VFSM.Done {-# INLINE [0] step #-} {-# INLINE [1] stream #-} rep :: Monad m => Int -> (Int -> m ()) -> m () rep n = flip VFSM.mapM_ (stream 0 n) {-# INLINE rep #-} streamR :: Monad m => Int -> Int -> VFSM.Stream m Int streamR !l !r = VFSM.Stream step (r - 1) where step x | x >= l = return $ VFSM.Yield x (x - 1) | otherwise = return VFSM.Done {-# INLINE [0] step #-} {-# INLINE [1] streamR #-} rev :: Monad m => Int -> (Int -> m ()) -> m () rev !n = flip VFSM.mapM_ (streamR 0 n) {-# INLINE rev #-} streamStep :: Monad m => Int -> Int -> Int -> VFSM.Stream m Int streamStep !l !r !d = VFSM.Stream step l where step x | x < r = return $ VFSM.Yield x (x + d) | otherwise = return VFSM.Done {-# INLINE [0] step #-} {-# INLINE [1] streamStep #-} bitReverse :: Int -> Int bitReverse = unsafeCoerce . step 32 0xffffffff00000000 0x00000000ffffffff . step 16 0xffff0000ffff0000 0x0000ffff0000ffff . step 08 0xff00ff00ff00ff00 0x00ff00ff00ff00ff . step 04 0xf0f0f0f0f0f0f0f0 0x0f0f0f0f0f0f0f0f . step 02 0xcccccccccccccccc 0x3333333333333333 . step 01 0xaaaaaaaaaaaaaaaa 0x5555555555555555 . unsafeCoerce where step :: Int -> Word64 -> Word64 -> Word64 -> Word64 step i ml mr = \ !x -> (x .&. ml) .>>. i .|. (x .&. mr) .<<. i {-# INLINE step #-} ------------------------------------------------------------------------------- isPrime :: Int -> Bool isPrime k | k <= 3 = k == 2 || k == 3 | even k = False | otherwise = millerRabin k where millerRabin :: Int -> Bool millerRabin n | n < 2047 = loop [2] | n < 1373653 = loop [2,3] | n < 9080191 = loop [31,73] | n < 25326001 = loop [2,3,5] | n < 4759123141 = loop [2,7,61] | n < 1122004669633 = loop [2,13,23,1662803] | n < 2152302898747 = loop [2,3,5,7,11] | n < 3474749660383 = loop [2,3,5,7,11,13] | n < 341550071728321 = loop [2,3,5,7,11,13,17] | otherwise = loop [2,325,9375,28178,450775,9780504,1795265022] where !m = n - 1 !s = countTrailingZeros m !d = m .>>. s check1 :: Int -> Bool check1 !a = powModInt a d n /= 1 {-# INLINE check1 #-} check2 :: Int -> Int -> Bool check2 !a !i = (powModInt a (d * (1 .<<. i)) n) /= m {-# INLINE check2 #-} loop [] = True loop (a:as) | check1 a && allok = False | otherwise = loop as where allok = all (check2 a) [0..(s - 1)]