Counting coins

The coin collection game wouldn't really be much of a game if there were only one coin. The central idea is that a level should feature many coins, all of which the player should collect before a timer expires. Now, to know whether all coins have been collected, we'll need to know how many coins there are in total in the scene. After all, if we don't know how many coins there are, then we can't know if we've collected them all. So, our first task in scripting is to configure the Coin class so that we can know the total number of coins in the scene at any moment easily. Consider Code Sample 2.3, which adapts the Coin class to achieve this:

//-------------------------
using UnityEngine;
using System.Collections;
//-------------------------
public class Coin : MonoBehaviour 
{
  //-------------------------
  //Keeps track of total coin count in scene
  public static int CoinCount = 0;
  //-------------------------
  // Use this for initialization
  void Start () 
{
    //Object...