Data commit

Task/Permutations/Lambdatalk/permutations-1.lambdatalk

@@ -0,0 +1,25 @@
+{def inject
+ {lambda {:x :a}
+  {if {A.empty? :a}
+   then {A.new {A.new :x}}
+   else {let { {:c {{lambda {:a :b} {A.cons {A.first :a} :b}} :a}}
+               {:d {inject :x {A.rest :a}}}
+               {:e {A.cons :x :a}}
+             } {A.cons :e {A.map :c :d}}}}}}
+-> inject
+
+{def permut
+ {lambda {:a}
+  {if {A.empty? :a}
+   then {A.new :a}
+   else {let { {:c {{lambda {:a :b} {inject {A.first :a} :b}} :a}}
+               {:d {permut {A.rest :a}}}
+             } {A.reduce A.concat {A.map :c :d}}}}}}
+-> permut
+
+{permut {A.new 1 2 3}}
+-> [[1,2,3],[2,1,3],[2,3,1],[1,3,2],[3,1,2],[3,2,1]]
+
+{permut {A.new 1 2 3 4}}
+->
+[[1,2,3,4],[2,1,3,4],[2,3,1,4],[2,3,4,1],[1,3,2,4],[3,1,2,4],[3,2,1,4],[3,2,4,1],[1,3,4,2],[3,1,4,2],[3,4,1,2],[3,4,2,1],[1,2,4,3],[2,1,4,3],[2,4,1,3],[2,4,3,1],[1,4,2,3],[4,1,2,3],[4,2,1,3],[4,2,3,1],[1,4,3,2],[4,1,3,2],[4,3,1,2],[4,3,2,1]]

Task/Permutations/Lambdatalk/permutations-2.lambdatalk

@@ -0,0 +1,69 @@
+1) permutations on sentences
+
+{script
+  var S_perm = function(a) {
+    if (a.length < 2) return [a];
+    var b = [];
+    for (var c = 0; c < a.length; c++) {
+        var e = a.splice(c, 1), f = S_perm(a);
+        for (var d = 0; d < f.length; d++)
+           b.push( e.concat( f[d]) );
+        a.splice(c, 0, e[0])
+    }
+    return b
+  }
+
+  LAMBDATALK.DICT['S.perm'] = function() {  // {S.perm 1 2 3}
+    return S_perm( arguments[0].trim()
+                               .split(" ") )
+                               .join(" ")
+                               .replace(/\s/g,"{br}")
+  };
+}
+
+{S.perm 1 2 3}
+->
+1,2,3
+1,3,2
+2,1,3
+2,3,1
+3,1,2
+3,2,1
+
+{S.perm hello brave world}
+->
+hello,brave,world
+hello,world,brave
+brave,hello,world
+brave,world,hello
+world,hello,brave
+world,brave,hello
+
+2) permutations on words
+
+{script
+  var W_perm = function(word) {
+    if (word.length === 1) return [word]
+    var results = [];
+    for (var i = 0; i < word.length; i++) {
+      var buti = W_perm( word.substring(0, i) + word.substring(i + 1) );
+      for (var j = 0; j < buti.length; j++)
+        results.push(word[i] + buti[j]);
+    }
+    return results;
+  };
+
+  LAMBDATALK.DICT['W.perm'] = function() {  // {W.perm 123}
+    return W_perm( arguments[0].trim() ).join("{br}")
+  };
+
+}
+
+{W.perm 123}
+->
+123
+132
+213
+231
+312
+321