Java求解大整数问题：利用BigInteger类

import java.util.Scanner;
import java.math.*;
public class Main{
	public static void main(String[] args){
		Scanner input = new Scanner(System.in);
		while (input.hasNext()){
			int n;
			BigInteger a,b;
			n=input.nextInt();
			a=input.nextBigInteger();
			b=input.nextBigInteger();
			System.out.println(a.multiply(b));
		}
	}
}