Spawn a number of enemy's on the map

Questions & Answers
1

Hello I am making a zombie survival game and I want to Spawn a number of enemy’s on the map can you help here is my code I am using unity 5 thank you.

using UnityEngine;
using System.Collections;

public class GameManagement : MonoBehaviour {
	public int round = 1;
	int zombesInRound = 5;
	int zombiesSpawnInRound = 0;
	float zombieSpawnTimer = 0;
	public Transform[] zombieSpawnPoints;
	public GameObject zombieEnemy;

	void Start () {
	
	}
	

	void Update () {
		if (zombiesSpawnInRound < zombesInRound)
		{
			if(zombieSpawnTimer > 30)
			{
				SpawnZombie ();
				zombieSpawnTimer = 0;
			}
			else
			{
				zombieSpawnTimer++;
			}
		}
	}
	void SpawnZombie()
	{
		Vector3 randomSpawnPiont = zombieSpawnPoints[Random.Range (0, zombieSpawnPoints.Length)].position;
		Instantiate(zombieEnemy,randomSpawnPiont,Quaternion.identity);
		zombesInRound ++;
	}
}
2

You might consider using two variables for your zombie spawn rate.

public float zombieSpawnRate = 5.0f; // One every X seconds
float zombieSpawnTimer;

void Start()
{
    zombieSpawnTimer = zombieSpawnRate;
}

void Update()
{
    if(zombiesSpawnInRound < zombiesInRound)
    {
        if(zombieSpawnTimer <= 0)
        {
            SpawnZombie();
            zombieSpawnTimer = zombieSpawnRate;
        }
        // If used here, timer will wait at X seconds
        // before a new zombie can spawn when at the
        // maximum possible in the round
        zombieSpawnTimer -= Time.deltaTime;
    }
    // If used here, zombie can spawn
    // instantly upon another's death when
    // at the maximum in the round
    // zombieSpawnTimer -= Time.deltaTime;
}