Rot13 = {
	map: null,

	convert: function(a) {
		Rot13.init();

		var s = "";
		for (i=0; i < a.length; i++) {
			var b = a.charAt(i);
			s += ((b>='A' && b<='Z') || (b>='a' && b<='z') ? Rot13.map[b] : b);
		}
		return s;
	},

	init: function() {
		if (Rot13.map != null)
			return;

		var map = new Array();
		var s   = "abcdefghijklmnopqrstuvwxyz";

		for (i=0; i<s.length; i++)
			map[s.charAt(i)] = s.charAt((i+13)%26);
		for (i=0; i<s.length; i++)
			map[s.charAt(i).toUpperCase()] = s.charAt((i+13)%26).toUpperCase();

		Rot13.map = map;
	},

	write: function(a) {
		document.write(Rot13.convert(a));
	}
}