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Microsoft Azure Notebooks - Live code - F#, R, and Python

I was exploring Jupyter notebooks , that combines live code, markdown and data, through Microsoft's implementation, known as MS Azure Notebooks , putting together a small library of R and F# notebooks . As Microsoft's FAQ for the service describes it as : ...a multi-lingual REPL on steroids. This is a free service that provides Jupyter notebooks along with supporting packages for R, Python and F# as a service. This means you can just login and get going since no installation/setup is necessary. Typical usage includes schools/instruction, giving webinars, learning languages, sharing ideas, etc. Feel free to clone and comment... In R Azure Workbook for R - Memoisation and Vectorization Charting Correlation Matrices in R In F# Charnownes Constant in FSharp.ipynb Project Euler - Problems 18 and 67 - FSharp using Dynamic Programming
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Project Euler - Problem #36


Description
  • The decimal number, 585 = 1001001001 (binary), is palindromic in both bases.
  • Find the sum of all numbers, less than one million, which are palindromic in base 10 and base 2.
  • (Please note that the palindromic number, in either base, may not include leading zeros.)

Solution (Improved)

let isPalindromicBase2 (n:int) =
     let forward = System.Convert.ToString(n,2) |> Seq.map (fun c -> int c - int '0') |> Seq.toArray
     let rev = Array.rev forward
     if forward = rev then
          true
     else
         false

let reverse (s:string) = new string(s |> Seq.toArray |> Array.rev)

let getPalindromesBase10 =
     let base10Array = [|1..1000000|] |> Array.filter (fun x -> string x = reverse(string x))
     let base02Array = base10Array |> Array.filter (fun x -> isPalindromicBase2  x)
     Array.sum base02Array

Solution (Original)

let reverseToBinaryList (n:int) =
     System.Convert.ToString(n,2)
     |> Seq.map (fun c -> int c - int '0')
     |> Seq.toArray
     |> Array.rev

let convertToBinaryList (n:int) =
     System.Convert.ToString(n,2)
     |> Seq.map (fun c -> int c - int '0')
     |> Seq.toArray

let reverse (s:string) = new string(s |> Seq.toArray |> Array.rev)

let getPalindromesBase10 =
     let base10Array = [|1..1000000|]
     |> Array.filter (fun x -> string x = reverse(string x))
     let base02Array = base10Array
     |> Array.filter (fun x -> convertToBinaryList x = reverseToBinaryList x)
     Array.sum base02Array

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