if ((Input.GetKey (KeyCode.W)||Input.GetKey (KeyCode.UpArrow)) && (jumpTimer > 0)) {

            rigidbody2D.AddForce (new Vector2(0f,jumpForce));
        }

        if (grounded == false) {
                        jumpTimer -= Time.deltaTime;
                } else
        {
            jumpTimer = per;
        }