Java scanner有时需要输入两次

import java.util.Scanner;

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

        System.out.print("请输入一个整数：");
        int num1 = scanner.nextInt();

        System.out.print("请再次输入一个整数：");
        int num2 = scanner.nextInt();

        int sum = num1 + num2;
        System.out.println("两个整数的和为：" + sum);

        scanner.close();
    }
}