JAVA 大数总结

先留下一段代码，以后再写

HDU 1042 N!

import java.io.BufferedInputStream;
import java.math.BigInteger;
import java.util.Scanner;

public class Main {
    public static void main(String args[]){
        Scanner cin = new Scanner(new BufferedInputStream(System.in));
        while(cin.hasNextBigInteger()){
            BigInteger s = cin.nextBigInteger();
            BigInteger one = BigInteger.valueOf(1);
            BigInteger ans = BigInteger.valueOf(1);
            BigInteger tmp = BigInteger.valueOf(1);
            for(;tmp.compareTo(s)<=0;){
                ans=ans.multiply(tmp);
                tmp=tmp.add(one);
                //System.out.println(tmp);
            }
            System.out.println(ans);
        }
    }
}