Submission #54662401

---

Source Code Expand

import Data.Array
import Data.List
import Data.List.Split

main :: IO ()
main = do
  [n,m,k] <- getLnInts
  let ans = abc358f n m k
  putStrLn ans

getLnInts :: IO [Int]
getLnInts = map read . words <$> getLine

abc358f :: Int -> Int -> Int -> String
abc358f n m k =
  case mkRoute of
    Nothing     -> "No"
    Just (_:ds) -> unlines $ ("Yes" :) $ enStr $ mkMaze ds
  where
    mkRoute
      | k < n = Nothing -- 届かないパターン
      | odd n /= odd k = Nothing -- 偶奇が異なるパターン
      | odd n, even m, k >= n * m = Nothing -- 1マス埋められないパターン
      | odd n, k <= 1 + pred n * m = Just $ 'd' : doEven (pred n) (pred k) -- 偶数と同じで済むパターン
      | odd n = Just $ 'b' : doOdd -- 奇数で面倒なパターン
      | otherwise = Just $ doEven n k -- 偶数のパターン
    doEven 0 0 = ""
    doEven n1 k1 = 'D' : replicate w 'L' ++ 'D' : replicate w 'R' ++ doEven (n1 - 2) (k1 - 2 * succ w)
      where
        w = min (pred m) $ div (k1 - n1) 2
    doOdd = 'D' : loop (k - 3 - (n-3) * m) (doEven (n-3) ((n-3) * m))
    loop x rest
      | x >= 6 = "LULD" ++ loop (x - 6) ("RR" ++ rest)
      | x == 4 = "LLDRR" ++ rest
      | x == 2 = "LDR" ++ rest
      | x == 0 = 'D' : rest
    enStr arr = chunksOf (m + succ m) $ elems arr
    mkMaze ds = accumArray (flip const) '+' ((-1,-1),(n + pred n, m + pred m)) $
                ((-1, 2 * pred m), 'S') : ((n + pred n, 2 * pred m), 'G') :
                [((i,j),'o') | i <- [0, 2 .. 2 * pred n], j <- [0, 2 .. 2 * pred m]] ++
                [((i,j),'|') | i <- [0, 2 .. 2 * pred n], j <- [1, 3 .. 2 * pred m]] ++
                [((i,j),'-') | i <- [1, 3 .. 2 * pred n], j <- [0, 2 .. 2 * pred m]] ++
                [( ij  ,'.') | ij <- decode ds]
    decode ds = snd $ mapAccumL step (0, 2 * pred m) ds
      where
        step (i,j) 'D' = ((i+2,j),(i+1,j))
        step (i,j) 'U' = ((i-2,j),(i-1,j))
        step (i,j) 'L' = ((i,j-2),(i,j-1))
        step (i,j) 'R' = ((i,j+2),(i,j+1))

Submission Info

Compile Error

app/Main.hs:16:3: warning: [-Wincomplete-patterns]
    Pattern match(es) are non-exhaustive
    In a case alternative:
        Patterns of type ‘Maybe [Char]’ not matched: Just []
   |
16 |   case mkRoute of
   |   ^^^^^^^^^^^^^^^...

app/Main.hs:32:5: warning: [-Wincomplete-patterns]
    Pattern match(es) are non-exhaustive
    In an equation for ‘loop’:
        Patterns of type ‘a’, ‘[Char]’ not matched: _ _
   |
32 |     loop x rest
   |     ^^^^^^^^^^^...

app/Main.hs:46:9: warning: [-Wincomplete-patterns]
    Pattern match(es) are non-exhaustive
    In an equation for ‘step’:
        Patterns of type ‘(a, b)’, ‘Char’ not matched:
            (_, _) p where p is not one of {'R', 'L', 'D', ...}
   |
46 |         step (i,j) 'D' = ((i+2,j),(i+1,j))
   |         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...

Judge Result