Class Notes for While Loops

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        // While Loops - are event or condition controlled loops
        //            BUT can also be designed as count controlled
        // Always make sure you provide a way for the while loop
        // to exit inside the loop; otherwise you will create
        // an infinite loop (which is bad [usually]).
        
        // This is a while loop designed to be a count controlled loop
        // We know how many times this loop will run (10).
        // while ( THIS CONDITION IN HERE IS TRUE) { LOOP THIS }
        int i = 0;
        
        while (i<10){
            i++;
            System.out.print(i+" ");
        }
        
        System.out.println();
        
        // This is a while loop designed as an event controlled loop
        // The loop will exit if the user inputs anything less then 0
        Scanner keyboard = new Scanner(System.in);
        int j = 0;
        int sum = 0;
        
        while (j >= 0){
            System.out.print("Type in an integer to add to "+sum+" (-1 to EXIT): ");
            j = keyboard.nextInt();
            if(j >= 0){
                sum += j;
            }
        }
        
        System.out.println("Your Sum is: " + sum);
        
        // The Do While loop is the same as a while loop, but it is
        // guaranteed to run at least once; the condition is checked
        // after the loop is run NOT before it.
        int k = 0;
        
        do{
            System.out.print(k+" ");
            k--;
        } while(k>0);
        
        System.out.println();

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