24 game: Difference between revisions
m
→{{header|Koka}}
Line 6,513:
enter expression using [2,5,8,9] => (8 + 9) + (5 + 2)
you won!</pre>
=={{header|Koka}}==
<syntaxhighlight lang=koka>
import std/num/random
import std/os/readline
type expr
Num(i: int)
Add(e1: expr, e2: expr)
Sub(e1: expr, e2: expr)
Mul(e1: expr, e2: expr)
Div(e1: expr, e2: expr)
fun genNum()
random-int() % 9 + 1
fun parseFact(s: string): <div,exn> (expr, string)
match s.head
"(" ->
val (e, rest) = s.tail.parseExpr()
match rest.head
")" -> (e, rest.tail)
_ -> throw("expected ')'")
x | x.head-char.default('_').is-digit -> (Num(x.parse-int.unjust), s.tail)
_ -> throw("No factor")
fun parseTerm(s): <div,exn> (expr, string)
val (e', n) = s.parseFact()
match n.head
"*" ->
val (e'', n') = n.tail.parseTerm()
(Mul(e', e''), n')
"/" ->
val (e'', n') = n.tail.parseTerm()
(Div(e', e''), n')
_ -> (e', n)
fun parseExpr(s): <div,exn> (expr, string)
val (e', n) = s.parseTerm()
match n.head
"+" ->
val (e'', n') = n.tail.parseExpr()
(Add(e', e''), n')
"-" ->
val (e'', n') = n.tail.parseExpr()
(Sub(e', e''), n')
_ -> (e', n)
fun numbers(e: expr): div list<int>
match e
Num(i) -> [i]
Add(e1, e2) -> numbers(e1) ++ numbers(e2)
Sub(e1, e2) -> numbers(e1) ++ numbers(e2)
Mul(e1, e2) -> numbers(e1) ++ numbers(e2)
Div(e1, e2) -> numbers(e1) ++ numbers(e2)
fun check(e: expr, l: list<int>): <div,exn> ()
val ns = numbers(e)
if (ns.length == 4) then
if l.all(fn(n) ns.any(fn(x) x == n)) then
()
else
throw("wrong numbers")
else
throw("wrong number of numbers")
fun evaluate(e: expr): float64
match e
Num(i) -> i.float64
Add(e1, e2) -> evaluate(e1) + evaluate(e2)
Sub(e1, e2) -> evaluate(e1) - evaluate(e2)
Mul(e1, e2) -> evaluate(e1) * evaluate(e2)
Div(e1, e2) -> evaluate(e1) / evaluate(e2)
fun main()
println("\nGoal: ")
println("- Create an expression that evaluates to 24")
println("- Using the four given numbers each number once")
println("- Using the operators (+-/*) with no spaces")
println("Example 2 3 4 1: (2+3)*4*1\n")
println("Here are your numbers!")
var l: list<int> := Nil
repeat(4) fn()
val n = genNum()
l := Cons(n, l)
(n.show ++ " ").print
println("")
var found := False
while { !found } fn()
val (expr, r) = readline().parseExpr()
if r.count > 0 then
println("Expected EOF but got: " ++ r ++ " please try again")
return ()
expr.check(l)
val result = expr.evaluate()
if result == 24.0 then
println("You got it!")
found := True
else
println("Try again, your expression evaluated to: " ++ result.show)
</syntaxhighlight>
=={{header|Kotlin}}==
| |||