Error CS0103: The name `ctn' does not exist in the current context ??

I've been following the BurgZergArcade tutorials, I even bought the script package hoping for help (also cause the series is awesome and kudos were required). But I'm stumped.

I'm getting 3 errors that are all the same, just showing up in different areas. Assets/scripts/Character Classes/BaseCharacter.cs(71,32): error CS0103: The name `ctn' does not exist in the current context

Here's what I believe to be the problem code, though I'll post the whole file below incase I missed something.

     private void SetupPrimaryAttributes() {
         for(int cnt = 0; cnt < _primaryAttribute.Length; cnt++) {
             _primaryAttribute[ctn] = new Attribute();
         }
     }
     
     private void SetupVitals() {
         for(int cnt = 0; cnt < _vital.Length; cnt++) {
             _vital[ctn] = new Vital();
         }
     }
     
     private void SetupSkills() {
         for(int cnt = 0; cnt < _skill.Length; cnt++) {
             _skill[ctn] = new Skill();
         }
     }

And the whole file: using UnityEngine; using System.Collections; using System.Collections.Generic; using System; //added to access the enum class

 public class BaseCharacter : MonoBehaviour {
     private string _name;
     private int _level;
     private uint _freeExp;
     
     private Attribute [] _primaryAttribute;
     private Vital[] _vital;
     private Skill[] _skill;
     
     public void Awake() {
         _name = string.Empty;
         _level = 0;
         _freeExp = 0;
         
         _primaryAttribute = new Attribute[Enum.GetValues(typeof(AttributeName)).Length];
         _vital = new Vital[Enum.GetValues(typeof(VitalName)).Length];
         _skill = new Skill[Enum.GetValues(typeof(SkillName)).Length];
         
         SetupPrimaryAttributes();
         SetupVitals();
         SetupSkills();
     }
     
     
     public string Name {
         get{ return _name; }
         set{ _name = value; }
     }
     
     public int Level {
         get{ return _level; }
         set{ _level = value; }
     }
     
     public uint FreeExp {
         get{ return _freeExp; }
         set{ _freeExp = value; }
     }
     
     public void AddExp(uint exp) {
         _freeExp += exp;
         
         CalculateLevel();
     }
     
     
     //take average of all of the players skills and assign that as the player level.
     public void CalculateLevel() {
     }
     //
     
     private void SetupPrimaryAttributes() {
         for(int cnt = 0; cnt < _primaryAttribute.Length; cnt++) {
             _primaryAttribute[ctn] = new Attribute();
         }
     }
     
     private void SetupVitals() {
         for(int cnt = 0; cnt < _vital.Length; cnt++) {
             _vital[ctn] = new Vital();
         }
     }
     
     private void SetupSkills() {
         for(int cnt = 0; cnt < _skill.Length; cnt++) {
             _skill[ctn] = new Skill();
         }
     }
     
     public Attribute GetPrimaryAttribute(int index) {
         return _primaryAttribute[index];
     }
     
     public Vital GetVital(int index) {
         return _vital[index];
     }
     
     public Skill GetSkill(int index) {
         return _skill[index];
     }
 
     private void SetupVitalModifiers() {
         //health
         GetVital((int)VitalName.Health).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Constitution), .5f));
         
         //energy
         GetVital((int)VitalName.Energy).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Constitution), 1));
         //mana
         GetVital((int)VitalName.Mana).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Willpower), 1));
     }
     
     private void SetupSkillModifiers() {
         //melee offence
         GetSkill((int)SkillName.Melee_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Might), .33f));
         GetSkill((int)SkillName.Melee_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Nimbleness), .33f));
         
         //melee defence
         GetSkill((int)SkillName.Melee_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Speed), .33f));
         GetSkill((int)SkillName.Melee_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Constitution), .33f));
         
         //magic offence
         GetSkill((int)SkillName.Magic_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Concentration), .33f));
         GetSkill((int)SkillName.Magic_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Willpower), .33f));
         
         //magic defence
         GetSkill((int)SkillName.Magic_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Concentration), .33f));
         GetSkill((int)SkillName.Magic_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Willpower), .33f));
         
         //ranged offence
         GetSkill((int)SkillName.Ranged_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Concentration), .33f));
         GetSkill((int)SkillName.Ranged_Offence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Speed), .33f));
         
         //ranged defence
         GetSkill((int)SkillName.Ranged_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Speed), .33f));
         GetSkill((int)SkillName.Ranged_Defence).AddModifier(new ModifyingAttribute(GetPrimaryAttribute((int)AttributeName.Nimbleness), .33f));
     }
     
     public void StatUpdate() {
         for(int cnt = 0; cnt < _vital.Length; cnt++)
             _vital[cnt].Update();
         for(int cnt = 0; cnt < _skill.Length; cnt++)
             _skill[cnt].Update();
     }
 
 }

I'm new at coding all together and slapping my head, bleh!! D: