open System

open System.Text

open System.IO

​

open Newtonsoft.Json

open Newtonsoft.Json.Linq

open Newtonsoft.Json.Converters

open Newtonsoft.Json.Serialization

​

// https://stackoverflow.com/questions/61288900/how-do-i-make-a-for-loop-that-scans-through-a-json-in-f

​

//https://www.newtonsoft.com/json/help/html/DeserializeWithJsonSerializerFromFile.htm

let jsonFromFile<'T>(fileName : string, settings : JsonSerializerSettings) = 

    use streamReader = new StreamReader(fileName)

    use jsonReader = new JsonTextReader(streamReader)

    let serializer = JsonSerializer.CreateDefault(settings)

    serializer.Deserialize<'T>(jsonReader)

​

let fileName = "question61288900.json"

let originalJsonString = "{\"1\":[29,30,41,48,64],\"2\":[29,320,441,548,11],\"3\":[29,3202,4421,5428,141]}"

​

File.WriteAllText(fileName, originalJsonString)

​

let requiredValues = [29;30;41;48;64] // Or whatever list of values you are looking for

​

let map = jsonFromFile<Map<string, int list>>(fileName, null)

​

let filteredMap = 

    map |> Map.toSeq

        |> Seq.filter (fun (key, value) -> requiredValues = value)

        |> Map.ofSeq

​

// Print results

filteredMap |> Map.iter (fun key value ->

   printf "Key = %A has matching list of values = %A\n" key value)

​

​