tasks a-s

Task/Palindrome-detection/GAP/palindrome-detection.gap

@@ -0,0 +1,27 @@
+ZapGremlins := function(s)
+  local upper, lower, c, i, n, t;
+  upper := "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
+  lower := "abcdefghijklmnopqrstuvwxyz";
+  t := [ ];
+  i := 1;
+  for c in s do
+    n := Position(upper, c);
+    if n <> fail then
+      t[i] := lower[n];
+      i := i + 1;
+    else
+      n := Position(lower, c);
+      if n <> fail then
+        t[i] := c;
+        i := i + 1;
+      fi;
+    fi;
+  od;
+  return t;
+end;
+
+IsPalindrome := function(s)
+  local t;
+  t := ZapGremlins(s);
+  return t = Reversed(t);
+end;