Consider the following expression:
     int limit = 9;
     for(int i = 3; i <= limit; i++){...}




1. Now let's remove the noise and extract the core logic:

     i  <=  limit  ;   i++

     3  <=    9    ;   i++




2. And instead of thinking numerically, lets visualize it:


     index            ___i_______________       i= 3     Point you choose to start

     vector           ___i-------------->       i ++     Direction for iterations

     limit            ___i-----<=________       <= 9     End point of the operation


            The code runs *FOR* all items in this range:  ___i-----<=________




3. Think how do you want to break the operation:

     stop before limit?
                    use  <
                            i, 4, 5, 6, 7, 8      <  9
     execute at limit?
                    use  <=
                            i, 4, 5, 6, 7, 8, 9   <=  9