Java 2个（多个）大整数相加如何实

Answer 1

import java.util.Scanner;

public class Add{

　　public static void mian(String[] args) {
　　　　 System.out.println("请输入被加数a：");
Scanner scanner1 = new Scanner(System.in);

int num1 = scanner1.nextInt();
System.out.println("请输入被加数b");
Scanner scanner2 = new Scanner(System.in);

int num2 = scanner2.nextInt();
int sum = add(num1,num2);
System.out.println("a + b = " + sum);

}

static int add(int a, int b) {
return a+b;
}

}

Answer 2

说啥？