jdh30

open Printf

type expr =
  | Int of int
  | Var of string
  | Add of expr * expr
  | Mul of expr * expr
  | Pow of expr * expr
  | Ln of expr

jdh30

enum Expr {
  case Int(n: Int)
  case Var(x: String)
  indirect case Add(f: Expr, g: Expr)
  indirect case Mul(f: Expr, g: Expr)
  indirect case Pow(f: Expr, g: Expr)
  indirect case Ln(f: Expr)
}

func pown(a: Int, b: Int) -> Int {

jdh30

# .NET Core 2.1 with Ubuntu Server 18.04 - Version 1.0 - ami-f4f4cf91
sh <(curl -sL https://raw.githubusercontent.com/ocaml/opam/master/shell/install.sh)
sudo apt-get update
sudo apt-get install make m4 gcc zip aspcud emacs libssl-dev ncurses-dev pkg-config tuareg-mode libffi-dev bubblewrap linux-tools-common linux-tools-aws
opam init
eval $(opam env)
opam install ocamlfind core async async_ssl cohttp yojson ppx_deriving ocp-indent merlin cohttp-async

jdh30

// This code implements a persistent dictionary similar to Map except the
// internal representation is a Dictionary + diffs. This offers different
// performance tradeoffs and, in particular, much faster add and remove when
// used linearly.
//
// For more details, see the following articles from the F# Journal:
//
// http://fsharpnews.blogspot.co.uk/2017/10/the-concestor-set.html
// http://fsharpnews.blogspot.co.uk/2017/10/a-simple-concestor-dictionary.html

jdh30

    > let alpha = set['a'..'z'] + set['A'..'Z'];;

    > let num = set['0'..'9'];;

    > let alphanum = alpha + num;;

    > let (|Char|_|) alphabet = function
        | c::cs when Set.contains c alphabet -> Some(c, cs)
        | _ -> None;;

jdh30

    {
    open Parse
    open Lexing
    let ident = function
      | "let" -> LET
      | "rec" -> REC
      | "in" -> IN
      | "fun" -> FUN
      | "if" -> IF
      | "then" -> THEN

jdh30

    > let pInt : Parser<_, unit> = puint32 |>> int .>> spaces;;

    > let str s = pstring s >>. spaces;;

    > let keywords =
        "if then else let rec in fun".Split ' '
        |> set;;

    > let pIdent : Parser<_, unit> =

jdh30

>>>+[[-]>>[-]++>+>+++++++[<++++>>++<-]++>>+>+>+++++[>
++>++++++<<-]+>>>,<++[[>[->>]<[>>]<<-]<[<]<+>>[>]>[<+
>-[[<+>-]>]<[[[-]<]++<-[<+++++++++>[<->-]>>]>>]]<<]<]
<
[[<]>[[>]>>[>>]+[<<]<[<]<+>>-]>[>]+[->>]<<<<[[<<]<[<]
+<<[+>+<<-[>-->+<<-[>+<[>>+<<-]]]>[<+>-]<]++>>-->[>]>
>[>>]]<<[>>+<[[<]<]>[[<<]<[<]+[-<+>>-[<<+>++>-[<->[<<
+>>-]]]<[>+<-]>]>[>]>]>[>>]>>]<<[>>+>>+>>]<<[->>>>>>>
>]<<[>.>>>>>>>]<<[>->>>>>]<<[>,>>>]<<[>+>]<<[+<<]<]

jdh30

typedef char C;typedef long I;
typedef struct a{I t,r,d[3],p[2];}*A;
#define P printf
#define R return
#define V1(f) A f(w)A w;
#define V2(f) A f(a,w)A a,w;
#define DO(n,x) {I i=0,_n=(n);for(;i<_n;++i){x;}}
I *ma(n){R(I*)malloc(n*4);}mv(d,s,n)I *d,*s;{DO(n,d[i]=s[i]);}
tr(r,d)I *d;{I z=1;DO(r,z=z*d[i]);R z;}
A ga(t,r,d)I *d;{A z=(A)ma(5+tr(r,d));z->t=t,z->r=r,mv(z->d,d,r);

jdh30

open System.Collections.Generic

/// Imperative depth-first search
let dfs (V, E) =
  let visited = HashSet(HashIdentity.Structural)
  let stack = Stack[V]
  while stack.Count > 0 do
    let u = stack.Pop()
    if not(visited.Contains u) then
      for v in E u do