DoubleJump

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class DoubleJump : MonoBehaviour {

    public float Force = 250;
    private bool isjump = false;
    private bool isdoublejump = false;

    Rigidbody rig;
	void Start () {
        rig = this.GetComponent<Rigidbody>();
	}
	
	// Update is called once per frame
	void Update () {
		if(Input.GetKeyDown(KeyCode.Space) )
        {
            if(!isjump)
            {
                rig.AddForce(Vector3.up * Force);
                isjump = true;
            }
            else
            {
                if (!isdoublejump)
                {
                    rig.AddForce(Vector3.up * Force);
                    isdoublejump = true;
                }
            }
        }
	}

    void OnCollisionEnter(Collision collision)
    {
        if(collision.collider.tag.CompareTo("Plane") == 0)
        {
            isjump = false;
            isdoublejump = false;
        }
    }
}