https://www.wjsmithconstruction.com/

let parseArrayToTuple (input: int cluster) = (input.[0], input.[1])

let getInput () = Console.ReadLine().Split(" ") |> Array.map int |> parseArrayToTuple

let rec gcd (input: int * int) = let alterable biggerNumber = 0 let variable smallerNumber = 0

in the event that (fst input) > (snd input)
    biggerNumber <-(fst input)
    smallerNumber <-(snd input)
else
    biggerNumber <-(snd input)
    smallerNumber <-(fst input)

let divisionResult = biggerNumber % smallerNumber

match (divisionResult = 0) with
| valid - > smallerNumber
| bogus - > gcd (smallerNumber, divisionResult)

getInput () |> gcd |> Console.WriteLine