URL

Design HashSet - LeetCode

Code

https://github.com/syohex/dotnet-study/tree/master/fsharp/leetcode/challenge/202305/design_hashset/main.fsx

type MyHashSet =
    { Table: int list[] }

    static member init() : MyHashSet = { Table = Array.init 1024 (fun _ -> [])}

    static member add (key: int) (s: MyHashSet) : MyHashSet =
        let index = (hash key) % 1024
        let lst = s.Table.[index]

        if List.contains key lst then
            s
        else
            let lst' = key :: lst
            s.Table.[index] <- lst'
            s

    static member remove (key: int) (s: MyHashSet) : MyHashSet =
        let index = (hash key) % 1024
        let lst = s.Table.[index]

        if List.contains key lst then
            let lst' = List.except [ key ] lst
            s.Table.[index] <- lst'
            s
        else
            s

    static member contains (key: int) (s: MyHashSet) : bool =
        let index = (hash key) % 1024
        let lst = s.Table.[index]
        List.contains key lst