Repetition of the program? [closed]

问题

I want to loop my program to repeat if the user inputs y the program will repeat over and over again ,but if the user finally inputs n the program will stop

import java.util.Scanner;
public class ReverseIt {

public static void main(String[] args) {

    Scanner sc = new Scanner (System.in);

    String name;
    System.out.println("Input Name");
    name = sc.nextLine();

    StringBuilder rev = new StringBuilder(name);


    System.out.println("NAME: "+name+"\n");

    System.out.println("REVERSE:" +rev.reverse()+"\n");

    System.out.println("Would you like to do it again?(Y/N)\n");

    char repeat;

    repeat = sc.next().charAt(0);


    if(repeat == 'n'){
        System.out.println("Program  Stopped");
    }
        while(repeat == 'y'){
            System.out.println("Input Name");
            name = sc.nextLine();
            System.out.println("NAME: "+name+"\n");

            System.out.println("REVERSE:" +rev.reverse()+"\n");

            System.out.println("Would you like to do it again?(Y/N)\n");
        }

}

回答1:

I would separate the code into a separate function, and call that function if the scanner returns a "y". For example:

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

String name;
System.out.println("Input Name");
name = sc.nextLine();

StringBuilder rev = new StringBuilder(name);


System.out.println("NAME: "+name+"\n");

System.out.println("REVERSE:" +rev.reverse()+"\n");

System.out.println("Would you like to do it again?(Y/N)\n");

char repeat;

repeat = sc.next().charAt(0);


if(repeat == 'n'){
    System.out.println("Program  Stopped");
}
    if(repeat == 'y'){

function();

    }

}

Hope that helps

回答2:

Basically, you could use a do-while loop...

do {
    //...
    System.out.println("Would you like to do it again?(Y/N)\n");
    String repeat = sc.next();
} while (repeat.equalsIgnoreCase("y"));

See The while and do-while Statements for more details...

回答3:

Because, the question has to be asked once, it must be use do while statement to achieve what you are looking for.

Code:

public static void main(String... args) {

    String name,finish;
    do{
    System.out.println("Input Name"); 
    Scanner sc = new Scanner(System.in);
    name = sc.nextLine();
    StringBuilder rev = new StringBuilder(name);
    System.out.println("NAME: " + name + "\n");
    System.out.println("REVERSE:" + rev.reverse() + "\n");
    System.out.println("Would you like to do it again?(Y/N)\n");
    finish = sc.next();
    }while(finish.equalsIgnoreCase("Y"));

}

来源：https://stackoverflow.com/questions/24543811/repetition-of-the-program

标签

java

loops

repeat