Java大数类BigInteger的应用：计算1到100的阶乘和

package homewordk1;

import java.math.*;

public Factorial {
    public static  void main(String args[]){
        BigInteger fact=new BigInteger("1"),sum=new BigInteger("0");
        int i=1;
        do{
            fact=fact.multiply(new BigInteger(i+""));
            sum=sum.add(fact);
            ++i;
        }while(i<=100);
        System.out.println(sum.toString());
    }
}