day night script errors

does anyone know what is wrong i keep getting errors on the private const I'm trying to make a day night cycle i got this script from someone on youtube and i keep getting errors

errors

Assets/SunTimeOfDay.cs(11,40): error CS0103: The name HOUR' does not exist in the current context Assets/SunTimeOfDay.cs(13,56): error CS0103: The name DAY' does not exist in the current context

Assets/SunTimeOfDay.cs(10,41): error CS0103: The name `MINUTE' does not exist in the current context

1. using UnityEngine; using System.Collections;

      public class SunTimeOfDay : MonoBehaviour {
            public Transform[] sun;
            public float dayCycleInMinutes = 1;
        
            private const float SECOND = 1;
            private const float Minute = 60 * SECOND;
            private const float Hour = 60 * MINUTE;
            private const float Day = 24 * HOUR;
        
            private const float DEGREES_PER_SECOND = 360 / DAY;
        
            private float _degreeRotation;
        
            private float _timeOfDay;
            
            // Use this for initialization
            void Start () {
                _timeOfDay = 0;
                _degreeRotation = DEGREES_PER_SECOND * Day /
    (dayCycleInMinutes * Minute);
            }
            
            // Update is called once per frame
            void Update () {
                sun [0].Rotate (new Vector3(_degreeRotation, 0, 0) *
    Time.deltaTime);
        
                _timeOfDay += Time.deltaTime;
                Debug.Log (_timeOfDay);
            }
        }