Initial data commit

Task/24-game/Sidef/24-game.sidef

@@ -0,0 +1,36 @@
+const digits  = (1..9 -> pick(4))
+const grammar = Regex(
+    '^ (?&exp) \z
+      (?(DEFINE)
+          (?<exp> ( (?&term) (?&op) (?&term) )+ )
+          (?<term> \( (?&exp) \) | [' + digits.join + '])
+          (?<op> [\-+*/] )
+      )', 'x'
+)
+
+say "Here are your digits: #{digits.join(' ')}"
+
+loop {
+    var input = read("Expression: ", String)
+
+    var expr = input
+    expr -= /\s+/g     # remove all whitespace
+
+    if (input == 'q') {
+        say "Goodbye.  Sorry you couldn't win."
+        break
+    }
+
+    var given_digits = digits.map{.to_s}.sort.join
+    var entry_digits = input.scan(/\d/).sort.join
+
+    if ((given_digits != entry_digits) || (expr !~ grammar)) {
+        say "That's not valid"
+        next
+    }
+
+    given(var n = eval(input)) {
+        when (24) { say "You win!"; break }
+        default   { say "Sorry, your expression is #{n}, not 24" }
+    }
+}