tasks a-s

Task/Power-set/ALGOL-68/power-set.alg

@@ -0,0 +1,27 @@
+MODE MEMBER = INT;
+
+PROC power set = ([]MEMBER s)[][]MEMBER:(
+  [2**UPB s]FLEX[1:0]MEMBER r;
+  INT upb r := 0;
+  r[upb r +:= 1] := []MEMBER(());
+  FOR i TO UPB s DO
+    MEMBER e = s[i];
+    FOR j TO upb r DO
+      [UPB r[j] + 1]MEMBER x;
+      x[:UPB x-1] := r[j];
+      x[UPB x] := e; # append to the end of x #
+      r[upb r +:= 1] := x # append to end of r #
+    OD
+  OD;
+  r[upb r] := s;
+  r
+);
+# Example: #
+test:(
+  [][]MEMBER set = power set((1, 2, 4));
+  FOR member TO UPB set DO
+    INT upb = UPB set[member];
+    FORMAT repr set = $"("f( upb=0 | $$ | $n(upb-1)(d", ")d$ )");"$;
+    printf(($"set["d"] = "$,member, repr set, set[member],$l$))
+  OD
+)