如何通过询问控制台中的用户是否要重复计算来执行一段代码

Question

I have written code that performs calculations by entering the console and now I want to ask the user if they want to perform this again by entering "Y" or "N" in the console.

I solved this part with a simple if statement, but now I want to execute the whole code above again in case the user enters "Y". Does anyone have a suggestion for this problem?

    System.out.println("Wollen Sie die Rechnung nocheinmal ausführen? Y / N");

    String yesorno2 = StdIn.readString();
    if (yesorno2.equals("Y")) {
        //Should repeat the code above
    } else {
        System.out.println("Auf Wiedersehn");
        //Should say the text above and end the code
    }
}

Answer 1

There are a few ways you could repeat the code above, depending on what you're trying to accomplish. One way would be to use a while loop that continues to execute the code as long as the user enters "Y". Here's an example:

while (yesorno2.equals("Y")) {
    // code to repeat goes here
    System.out.println("Wollen Sie die Rechnung nocheinmal ausführen? Y / N");
    yesorno2 = StdIn.readString();
}
System.out.println("Auf Wiedersehn");

Another way would be to use a do-while loop, like this:

do {
    // code to repeat goes here
    System.out.println("Wollen Sie die Rechnung nocheinmal ausführen? Y / N");
    yesorno2 = StdIn.readString();
} while (yesorno2.equals("Y"));
System.out.println("Auf Wiedersehn");

It's a good idea to wrap up the code that needs to be repeated in a function, so it could be easily called multiple times.

You also could use recursion, which is a technique that involves a function calling itself. This would also let you wrap up the code that needs to be repeated in a single function, but it can be more tricky to implement and can lead to stack overflow if not implemented correctly.