var cols = new Array("", false, false, false, false,false)

function checkField(which) {
	var which_col = which.id.split('_');
	
	if (!cols[which_col[1]]) {
		cols[which_col[1]] = true;
		return true;
	} else {
		alert("You can only sign up for one game per time slot.");
		return false;
	}	
	return false;
}

function checkSignup() {
	var name = document.getElementById('uname').value;
	if (name.length < 4) { 
		alert("Your name is required");
		return false;
	} else {
		return true;
	}
	return false;
}