// Rot13 encode and decode text.

function Rot13(input)
{
	var result = new String('');
	if(input.length > 0)
	{
		for(var i=0; i < input.length; i++)
		{
			var chr = input.charCodeAt(i);
			
			//lowerhalf inc by 13
			if((chr > 64 && chr < 78) || (chr > 96 && chr < 110)) 
				chr = chr + 13;
			
			// upperhalf dec by 13				
			else if((chr > 77 && chr < 91) || (chr > 109 && chr < 123)) 
				chr = chr - 13;
			
			result = result.concat(String.fromCharCode(chr));
		}
	}
	return result;
}