所有语句都被执行。没有案例的代码正在运行

Question

/*
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 * and open the template in the editor.
 */
package cities;

import java.util.Scanner;
import java.util.Vector;

public class Cities {

    public static void main(String a[]) {
        Scanner z = new Scanner(System.in);
        int x;
        String name, del;
        Vector<String> vct = new Vector<String>();
        vct.add("Los Angeles");
        System.out.println(vct);
        System.out.println("Select : \n1.Add City \n2.Remove City\n3.Display\n");
        x = z.nextInt();
        switch (x) {
            case 1:
                System.out.println("Enter a city name to add :");
                name = z.nextLine();

                if (vct.contains(name)) {
                    System.out.println("Already Exists.");

                } else {
                    vct.add(name);
                    System.out.println("Updated Vector :" + vct);
                    break;

                }


            case 2:
                System.out.println("Enter the city name to delete :");
                del = z.nextLine();
                vct.remove(del);
                System.out.println("Updated Vector :" + vct);
                break;

            case 3:
                System.out.println(vct);
                break;
            default:
                System.out.println("Please provide a proper input.");
                break;


        }


    }
}

Answer 1

您错过了案例1的结尾break;。