var username = document.getElementById('username');
            var password = document.getElementById('password');
            var password2 = document.getElementById('password-2');
            var rex = /^[a-zA-Z0-9]{3,10}$/i;
            if(rex.test(username.value) && password.value === password2.value && password.value.length >= 6 && password.value.length <= 20) {

                return true;
            }

            return false