My backpack script doubt

I made this simple backpack script, but as you can see I think I used too the statement "if", is another way to make with another statement like "for"? I'm not very good at programming ...

 #pragma strict

//Slot 1 var slot1 : String; var slot1cfg : float; var slot1cfg2 : float;

//Slot 2 var slot2 : String; var slot2cfg : float; var slot2cfg2 : float;

//Slot 3 var slot3 : String; var slot3cfg : float; var slot3cfg2 : float;

function Update(){

//Slot 1 if(!slot1){

slot1 = slot2; slot1cfg = slot2cfg;

slot2 =""; slot2cfg =0; slot2cfg2 =0;

}

//Slot 2 if(!slot2){

slot2 = slot3; slot2cfg = slot3cfg;

slot3 =""; slot3cfg =0; slot3cfg2 =0;

}

}

function Put(Name : String, cfg : float, cfg2 : float){

if(!slot1){

slot1 = Name; slot1cfg = cfg; slot1cfg2 = cfg2;

} else if(!slot2){

slot2 = Name; slot2cfg = cfg; slot2cfg2 = cfg2;

} else if(!slot3){

slot3 = Name; slot3cfg = cfg; slot3cfg2 = cfg2;

}

}