let ``No.179 塗り分け`` () =
    let bitcount (bit:int) =
        let a = (bit &&& 0x55555555) + (bit >>> 1 &&& 0x55555555) in
        let b = (a &&& 0x33333333) + (a >>> 2 &&& 0x33333333) in
        let c = (b &&& 0x0F0F0F0F) + (b >>> 4 &&& 0x0F0F0F0F) in
        let d = (c &&& 0x00FF00FF) + (c >>> 8 &&& 0x00FF00FF) in
        (d &&& 0x0000FFFF) + (d >>> 16 &&& 0x0000FFFF)
    let bc l = Seq.map bitcount l |> Seq.sum
    let arr = stdin.ReadLine().Split(' ')
    let H = int(arr.[0])
    let W = int(arr.[0])
    // '#' と '.' を数値 1 と 0 に変換 (ビットに変換する)。 
    let read() =
        stdin.ReadLine()
        |> Seq.mapi (fun i c -> (int(c)%46%34) <<< i)
        |> Seq.reduce (|||)
    let bits = [ for i in 1..H -> read() ]
    let mask = (1 <<< W) - 1
    let c1 = bc bits
    let p =
        if c1 &&& 1 = 1 then 0
        else
            let c2 = c1/2
            let check l = bc l = c2
            // 総当たり
            // 衝突判定があり、ビットの総数÷2の数になれば一致したとみなす。
            let b =
                seq { for h in 1..H do for w in 1..W -> h,w }
                |> Seq.collect (fun (h,w) ->
                    let blank = List.init h (fun _ -> 0)
                    let r = List.map (fun n -> n >>> w &&& mask) bits
                    let l = List.map (fun n -> n <<< w &&& mask) bits
                    seq [
                        yield check r                               // →
                        yield check l                               // ←
                        yield check ((List.skip h bits)@blank)      // ↑
                        yield check (blank@(List.take (H-h) bits))  // ↓
                        yield check ((List.skip h r)@blank)         // ↗
                        yield check ((List.skip h l)@blank)         // ↖
                        yield check (blank@(List.take (H-h) r))     // ↘
                        yield check (blank@(List.take (H-h) l))     // ↙
                    ]
                )
                |> Seq.exists id
            if b then 1 else 0
    printfn "%s" ["NO";"YES";].[p]
``No.179 塗り分け`` ()