Collecting specific number of specific items to win a game

Hello, I'm a beginner coder here, and I really don't know how to go about it sometimes... My game has 9 different collectibles that is displayed in an inventory panel, but for this scene, the player must collect only 6 "berry1" and 2 "egg1" in order to win this level. This is my pickup script for counting and displaying the collectibles; it is attached to the Player GameObject.

using UnityEngine; using UnityEngine.UI; using System.Collections;

public class pickup : MonoBehaviour {

 public GameObject inventoryPanel;
 public GameObject[] inventoryIcons;

 public GameObject gameWinScreen;

 void Start()
 {
     gameWinScreen.SetActive (false);
 }

 void OnCollisionEnter2D (Collision2D col)
 {

     //look through children for existing icon
     foreach (Transform child in inventoryPanel.transform) 
     {
         //if item is already in inventory
         if (child.gameObject.tag == col.gameObject.tag) 
         {
             string c = child.Find ("Text").GetComponent<Text> ().text;
             int tcount = System.Int32.Parse (c) + 1;
             child.Find ("Text").GetComponent<Text> ().text = "" + tcount;
             return;
         }

     }

     GameObject i;
     if (col.gameObject.tag == "berry1") 
     {
         i = Instantiate (inventoryIcons [0]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "berry2") 
     {
         i = Instantiate (inventoryIcons [1]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "berry3") 
     {
         i = Instantiate (inventoryIcons [2]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "egg1") 
     {
         i = Instantiate (inventoryIcons [3]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "egg2") 
     {
         i = Instantiate (inventoryIcons [4]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "herb1") 
     {
         i = Instantiate (inventoryIcons [5]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "herb2") 
     {
         i = Instantiate (inventoryIcons [6]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "herb3") 
     {
         i = Instantiate (inventoryIcons [7]);
         i.transform.SetParent (inventoryPanel.transform);
     }

     else if (col.gameObject.tag == "herb4") 
     {
         i = Instantiate (inventoryIcons [8]);
         i.transform.SetParent (inventoryPanel.transform);
     }
 }

 void Update () 
 {

     //if (??) 
     {
         gameWinScreen.SetActive (true);

         Time.timeScale = 0f;
     }
 }

}

How could I make it so when the count for berry1 and egg1 reaches 6 and 2 respectively, the gameWinScreen would be activated? I've been stuck on this for days... If anyone could help me with this, I couldn't be more grateful.