URL

https://leetcode.com/problems/design-circular-deque/description/?envType=daily-question&envId=2024-09-28

Code

https://github.com/syohex/dotnet-study/blob/master/fsharp/leetcode/challenge/202409/design_circular_deque/main.fsx

type MyCircularDeque =
    { Q: int[]
      Start: int
      End: int
      Capacity: int
      Size: int }

    static member Init(k: int) : MyCircularDeque =
        { Q = Array.zeroCreate k
          Start = 0
          End = k - 1
          Capacity = k
          Size = 0 }

    static member InsertFront (v: int) (q: MyCircularDeque) : bool * MyCircularDeque =
        if MyCircularDeque.IsFull q then
            false, q
        else
            let start = (q.Start - 1 + q.Capacity) % q.Capacity
            q.Q.[start] <- v

            true,
            { q with
                Q = q.Q
                Start = start
                Size = q.Size + 1 }

    static member InsertLast (v: int) (q: MyCircularDeque) : bool * MyCircularDeque =
        if MyCircularDeque.IsFull q then
            false, q
        else
            let end' = (q.End + 1) % q.Capacity
            q.Q.[end'] <- v

            true,
            { q with
                Q = q.Q
                End = end'
                Size = q.Size + 1 }

    static member DeleteFront(q: MyCircularDeque) : bool * MyCircularDeque =
        if MyCircularDeque.IsEmpty q then
            false, q
        else
            let start = (q.Start + 1) % q.Capacity

            true,
            { q with
                Start = start
                Size = q.Size - 1 }

    static member DeleteLast(q: MyCircularDeque) : bool * MyCircularDeque =
        if MyCircularDeque.IsEmpty q then
            false, q
        else
            let end' = (q.End - 1 + q.Capacity) + q.Capacity
            true, { q with End = end'; Size = q.Size - 1 }

    static member GetFront(q: MyCircularDeque) : int =
        if MyCircularDeque.IsEmpty q then -1 else q.Q.[q.Start]

    static member GetRear(q: MyCircularDeque) : int =
        if MyCircularDeque.IsEmpty q then -1 else q.Q.[q.End]

    static member IsEmpty(q: MyCircularDeque) : bool = q.Size = 0
    static member IsFull(q: MyCircularDeque) : bool = q.Size = q.Capacity