打比赛时候经常遇到运用大数据题目，又懒得敲那么长的代码，Java中有一个类就是用来处理很大的数据的类，为BigInteger类。
哈哈 省时省力
下面是BigInteger类常用的方法，基本上所有的操作要转换成BigInteger对象来进行处理
具体的测试代码如下：

import java.math.BigInteger;
public class Main {
   
    public static void main(String[] args) {
   
        //加法
        BigInteger add1 = new BigInteger("10");
        System.out.println(add1.add(new BigInteger("20")));
        
        //减法
        BigInteger sub1 = new BigInteger("10");
        System.out.println(sub1.subtract(new BigInteger("20")));
        
        //除法
        BigInteger div1 = new BigInteger("10");
        System.out.println(div1.divide(new BigInteger("20")));
        
        //乘法
        BigInteger mul1 = new BigInteger("10");
        System.out.println(mul1.multiply(new BigInteger("20")));
        
        //取模
        BigInteger remain1 = new BigInteger("10");
        System.out.println(remain1.remainder(new BigInteger("8")));
           
        //快速幂取模
        BigInteger mod = new BigInteger ("10");
        BigInteger pow = new BigInteger ("20");
        System.out.println(pow.modPow(pow,mod));
        
        //比较两个数字的大小,小于返回-1,大于返回1,等于0的时候返回0
        BigInteger comp1 = new BigInteger("10");
        System.out.println(comp1.compareTo(new BigInteger("18")));
        
        //n次幂的运算
        BigInteger power1 = new BigInteger("2");
        System.out.println(power1.pow(10));
        
        //返回较小的数
        BigInteger min1 = new BigInteger("2");
        System.out.println(min1.min(new BigInteger("-23")));
        
        //返回较大的数
        BigInteger max1 = new BigInteger("2");
        System.out.println(max1.max(new BigInteger("-23")));
        
        //返回该类型的数字的值
        BigInteger val = new BigInteger("123");
        System.out.println(val.intValue());
        
        //返回最大公约数
        BigInteger gcd1 = new BigInteger("12");
        System.out.println(gcd1.gcd(new BigInteger("6")));
        
        //取反
        BigInteger neg1 = new BigInteger("12");
        System.out.println(neg1.negate());
        
        //按位与
        BigInteger and1 = new BigInteger("10");
        System.out.println(and1.and(new BigInteger("1")));
        
        //按位或
        BigInteger or1 = new BigInteger("10");
        System.out.println(or1.or(new BigInteger("10")));
        
        //异或
        BigInteger xor1 = new BigInteger("10");
        System.out.println(xor1.xor(new BigInteger("10")));
        
        //返回n进制的字符串(进制的转换)
        BigInteger decimal1 = new BigInteger("12");
        System.out.println(decimal1.toString(2));
        
        //返回数字的绝对值
        BigInteger abs1 = new BigInteger("-12");
        System.out.println(abs1.abs());
        
        //检测某位上是否为1
        BigInteger testBit1 = new BigInteger("4");
        System.out.println(testBit1.testBit(2));  
 
       //左移1位
        BigInteger moveLeftBit1 = new BigInteger("4");
        System.out.println(moveLeftBit1.shiftLeft(1));
        
        //右移1位
        BigInteger moveRightBit1 = new BigInteger("4");
        System.out.println(moveRightBit1.shiftLeft(-1));
 
        //非
        BigInteger not = new BigInteger ("10");
        System.out.println(not.not());
 
        //valueOf()初始化
 
        //返回当前大整数的相反数
        BigInteger negate = new BigInteger ("10");
        System.out.println(negate.negate());
 
        //判断质数，并返回
        BigInteger prime = new BigInteger ("10");
        System.out.println(prime.probablePrime());
        System.out.println(prime.nextprobablePrime());
    }
}