URL

Design a Stack With Increment Operation - LeetCode

Code

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

type CustomStack =
    { Data: int[]
      Top: int }

    static member Init(maxSize: int) : CustomStack =
        { Data = Array.zeroCreate maxSize
          Top = -1 }

    static member Push (x: int) (s: CustomStack) : CustomStack =
        if s.Top + 1 < s.Data.Length then
            let top = s.Top + 1
            s.Data.[top] <- x
            { s with Data = s.Data; Top = top }
        else
            s

    static member Pop(s: CustomStack) : int * CustomStack =
        if s.Top >= 0 then
            let ret = s.Data.[s.Top]
            ret, { s with Top = s.Top - 1 }
        else
            -1, s

    static member Increment (k: int) (v: int) (s: CustomStack) : CustomStack =
        let len = min k (s.Top + 1)
        seq { 0 .. (len - 1) } |> Seq.iter (fun i -> s.Data.[i] <- s.Data.[i] + v)
        { s with Data = s.Data }