大数计算:import java.math.BigInteger;public class Temp5 {public static void main(String[] args) {BigInteger bigA = new BigInteger("1234567890"); // 实例化一个大数字BigInteger bigB = new BigInteger("9012345678912345"); // 实例化一个大数字System.out.println("加法操作:" +____________________);System.out.println("减法操作:"+ _____________________);System.out.println("做bigA的2次方操作:" +___________________);}}