import Data.Maybe
import Data.Char
import Data.Word
import qualified Data.IntMap.Strict as M
import qualified Data.ByteString.Char8 as C

parseInt :: C.ByteString -> Int
parseInt = fst . fromJust . C.readInt

suffixSums :: Int -> C.ByteString -> M.IntMap Int
suffixSums p s = snd $ C.foldr' acc ((1, 0), M.empty) s
  where
  acc c ((x, y), mp) = ((x', y'), M.alter f y' mp)
    where
    x' = 10 * x `mod` p
    y' = (x * digitToInt c + y) `mod` p
    f Nothing = Just 1
    f (Just cnt) = Just (cnt + 1)

fpm :: Int -> Int -> Int -> Int
fpm p a e
  | e == 0 = 1
  | otherwise = (if odd e then a * aa' else aa') `mod` p
  where
  aa = fpm p a $ e `div` 2
  aa' = aa * aa `mod` p

solve :: Int -> Int -> C.ByteString -> Word64
solve p pp s
  | n == 0 = 0
  | n == 1 = if parseInt s `mod` p == 0 then 1 else 0
  | otherwise = cnt + solve p pp x + solve p pp y
  where
  n = C.length s
  (x, y) = C.splitAt (n `div` 2) s
  mp = suffixSums p x
  cnt = snd $ C.foldl' acc ((0, 1), 0) y
  acc ((val, pow), total) c =
    let val' = (val * 10 + digitToInt c) `mod` p
        pow' = pow * pp `mod` p
        o = (p - val') * pow' `mod` p
    in ((val', pow'), total + (fromIntegral $ M.findWithDefault 0 o mp))

solve2 :: C.ByteString -> Word64
solve2 s
  | n == 0 = 0
  | n == 1 = if parseInt s `mod` 2 == 0 then 1 else 0
  | otherwise = fromIntegral (cnt * n') + solve2 x + solve2 y
  where
  n = C.length s
  n' = n `div` 2
  (x, y) = C.splitAt n' s
  cnt = C.foldl' acc 0 y
  acc total c = if digitToInt c `mod` 2 == 0 then total + 1 else total

main :: IO ()
main = do
  [_, p] <- map parseInt . C.words <$> C.getLine
  s <- C.getLine
  let pp = fpm p 10 (p - 2)
  putStrLn $ show $ (if p == 2 then solve2 s else solve p pp s)