tasks a-s

Task/Queue-Definition/GAP/queue-definition.gap

@@ -0,0 +1,35 @@
+Enqueue := function(v, x)
+   Add(v[1], x);
+end;
+
+Dequeue := function(v)
+   local n, x;
+   n := Size(v[2]);
+   if n = 0 then
+      v[2] := Reversed(v[1]);
+      v[1] := [ ];
+      n := Size(v[2]);
+      if n = 0 then
+         return fail;
+      fi;
+   fi;
+   return Remove(v[2], n);
+end;
+
+# a new queue
+v := [[], []];
+
+Enqueue(v, 3);
+Enqueue(v, 4);
+Enqueue(v, 5);
+Dequeue(v);
+# 3
+Enqueue(v, 6);
+Dequeue(v);
+# 4
+Dequeue(v);
+# 5
+Dequeue(v);
+# 6
+Dequeue(v);
+# fail