Java-on bizonyos mértékkel csökkenteni

mit szólnál valami ehhez hasonlóhoz:

public class loop {

    public enum Operation {INCREMENT, DECREMENT, INVALID}

    public static void main(String[] args) {
        Scanner scan = new Scanner(System.in);

        System.out.print("Update by (Increment/Decrement):");
        String operationString = scan.nextLine();

        System.out.print("Enter starting number:");
        String numberString = scan.nextLine();

        System.out.print("Enter update number:");
        String upnumberString = scan.nextLine();

        System.out.print("Enter end number:");
        String endnumberString = scan.nextLine();

        // Determine and parse stuff
        int startNumber = Integer.parseInt(numberString);
        int updateNumber = Integer.parseInt(upnumberString);
        int endNumber = Integer.parseInt(endnumberString);
        // Parse operation, but assume invalid operation
        Operation operation = Operation.INVALID;
        if (operationString.equalsIgnoreCase("increment")) {
            operation = Operation.INCREMENT;
        } else if (operationString.equalsIgnoreCase("decrement")) {
            operation = Operation.DECREMENT;
        }

        // now do the "meat" of the assignment
        int loopNumber = 0; // we'll keep the loop number as a separate counter
        switch (operation) {
            case INCREMENT:
                for (int i = startNumber; i < endNumber; i = i + updateNumber) {
                    loopNumber++;
                    performAssignmentPrinting(loopNumber, i);
                }
                break;

            case DECREMENT:
                for (int i = startNumber; i > endNumber; i = i - updateNumber) {
                    loopNumber++;
                    performAssignmentPrinting(loopNumber, i)
                }
                break;

            case INVALID:
            default:
                throw new IllegalStateException("Please enter supported operation! (increment/decrement)");
        }
    }

    private static void performAssignmentPrinting(int loopNumber, int value) {
        System.out.println("loop#" + loopNumber + "\tvalue=" + value);
    }
}

vagy a do/while verzió:

        // now do the "meat" of the assignment
        int currentNumber = startNumber;
        int loopNumber = 0; // we'll keep the loop number as a separate counter

        do {
            loopNumber++;
            switch (operation) {
                case INCREMENT:
                    currentNumber += updateNumber;
                    performAssignmentPrinting(loopNumber, currentNumber);
                    break;

                case DECREMENT:
                    currentNumber -= updateNumber;
                    performAssignmentPrinting(loopNumber, currentNumber);
                    break;

                case INVALID:
                default:
                    throw new IllegalStateException("Please enter supported operation! (increment/decrement)");
            }

        } while (currentNumber != endNumber);

i = i-3; cikluson kívül van. Az i dekrementációjának áthelyezése a ciklusba:

    do {
        System.out.println("loop#" + j + "\tvalue=" + i);
        j++;
        i = i - 3;
    } while (i > endnumber);

A for loop a megoldás a programodhoz. for(a ; b ; c) {...}
A for ciklus működése a Google-on. És próbáld megérteni, hogyan működik a 3 rész a,b,c.

Ál:

// if decrease mode
    // for (i = upperbound ; i >= lowerbound ; i-= decrement)
        // print i

// if increase mode
    // for (i = lowerbound ; i <= upperbound ; i+= increment)
        // print i

Frissítés: Ez elegendő ahhoz, hogy elinduljon, és további ellenőrzéseket adjon az utazáshoz.