如何從控制台讀取n個數字行？

Question

從控制台讀取所有行並存儲在 A 集合中。 在這種情況下如何使用掃描儀的方法。 用戶可以輸入的行數未知。

Answer 1

嘗試這個：

Scanner reader = new Scanner(System.in);
    List<String> a = new ArrayList<>();
    while (reader.hasNextLine()) {
        String s = reader.nextLine();
        if (s.equals("!q")) {
            break;
        }
        a.add(s);
    }

Answer 2

你可以試試這個：

import java.util.*;  
public class ScannerClassExample1 {    
      public static void main(String args[]){                       
          String s = "Hello, This is JavaTpoint.";  
          //Create scanner Object and pass string in it  
          Scanner scan = new Scanner(s);  
          //Check if the scanner has a token  
          System.out.println("Boolean Result: " + scan.hasNext());  
          //Print the string  
          System.out.println("String: " +scan.nextLine());  
          scan.close();           
          System.out.println("--------Enter Your Details-------- ");  
          Scanner in = new Scanner(System.in);  
          System.out.print("Enter your name: ");    
          String name = in.next();   
          System.out.println("Name: " + name);           
          System.out.print("Enter your age: ");  
          int i = in.nextInt();  
          System.out.println("Age: " + i);  
          System.out.print("Enter your salary: ");  
          double d = in.nextDouble();  
          System.out.println("Salary: " + d);         
          in.close();           
          }    
}  

和輸出將是這樣的：

Boolean Result: true
String: Hello, This is JavaTpoint.
-------Enter Your Details--------- 
Enter your name: Abhishek
Name: Abhishek
Enter your age: 23
Age: 23
Enter your salary: 25000
Salary: 25000.0