NullReferenceException: Object reference not set to an instance of an object

I've wasted many time trying to fix this I've been adding a player model and added a cube as an arm and made it as an arm and placed it in the character model but seriously I have no idea what so ever what to do. it told me to find an object update something and place the cube there I think here is the code

using UnityEngine; using System.Collections;

public class CharacterInputController : MonoBehaviour {

 private CharacterCollider character;
 private CharacterMotor motor;
 private CharacterMotorSwimming waterMotor;
 
 private Map map;
 private float jumpPressedTime = -100;

 // Use this for initialization
 void Awake() {
     character = GetComponent<CharacterCollider>();
     motor = GetComponent<CharacterMotor>();
     waterMotor = GetComponent<CharacterMotorSwimming>();
     map = (Map) GameObject.FindObjectOfType( typeof(Map) );
 }
 
 // Update is called once per frame
 void Update () {
     Vector3 direction = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
     direction = Vector3.ClampMagnitude(direction, 1);
     
     if(IsInWater()) {
         waterMotor.enabled = true;
         motor.enabled = false;
         
         waterMotor.inputEmersion = Input.GetButton("Jump");
         waterMotor.inputMoveDirection = transform.TransformDirection(direction);
         
         
     } else {
         waterMotor.enabled = false;
         motor.enabled = true;
         
         motor.inputMoveDirection = transform.TransformDirection(direction);
         
         if(Input.GetButtonDown("Jump")) {
             jumpPressedTime = Time.time;
         }
         if( !Input.GetButton("Jump") ) {
             jumpPressedTime = -100;
         }
         motor.inputJump = Time.time - jumpPressedTime <= 0.2f;
         motor.holdingInputJump = Input.GetButton("Jump");
     }
 }
 
 private bool IsInWater() {
     Vector3 bottom = transform.position;
     Vector3 top = bottom + Vector3.up*character.height;
     Vector3 pos = Vector3.Lerp(bottom, top, 0.2f);
     return map.GetBlock( Mathf.RoundToInt(pos.x), Mathf.RoundToInt(pos.y), Mathf.RoundToInt(pos.z) ).IsFluid();
 }
 

}