java的大数运算模板

import java.math.BigInteger;

import java.util.Scanner;

public class Main {

public static void main(String[] args) {

// TODO Auto-generated method stub

Scanner cin=new Scanner(System.in);

BigInteger a,b;

while(cin.hasNext())//等效于输入到文件尾

{

a=cin.nextBigInteger();

b=cin.nextBigInteger();

System.out.println(a.add(b));//输出a+b

System.out.println(a.subtract(b));//输出a-b

System.out.println(a.multiply(b));//输出a*b

System.out.println(a.divide(b));//输出a/b

System.out.println(a.remainder(b));//输出a%b

if(a.compareTo(b)==0)System.out.println("a==b");

if(a.compareTo(b)>0)System.out.println("a>b");

if(a.compareTo(b)<0)System.out.println("a<b");

System.out.println(a.abs());//大数a的绝对值

int exponent=cin.nextInt();

System.out.println(a.pow(exponent)); //大整数a的exponent次幂

//返回大整数十进制的字符串表示

System.out.println(a.toString());

//返回大整数p进制的字符串表示

int p=cin.nextInt();

System.out.println(a.toString(p));

}

}

}