BigInteger测试例子

import java.math.BigInteger;   
  
public class BigIntegerTest {   
  public static BigInteger lotteryOdds(int high, int number) {   
    BigInteger r = new BigInteger("1");   
    int i;   
    for (i = 1; i <= number; i++) {   
      r = r.multiply(BigInteger.valueOf(high)).divide(   
          BigInteger.valueOf(i));   
      high--;   
    }   
    return r;   
  }   
  
  public static void main(String[] args) {   
    int numbers = 100;   
    //("How many numbers do you need to draw?");   
    int topNumber = 100;   
    //"What is the highest number you can draw?");   
    BigInteger oddsAre = lotteryOdds(topNumber, numbers);   
  
    System.out.println("Your odds are 1 in " + oddsAre + ". Good luck!");   
  }   
}