Java代碼
/*
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package test;
import java.math.BigInteger;
import java.math.BigDecimal;
/**
* 2011-3-19
* @author Jasper
*/
public class RedandBlue {
public static void main(String[] args) {
System.out.println(“雙色球中獎概率（6/33+1/16）：”);
BigInteger allOdds = getOdds(33,6).multiply(getOdds(16,1));
BigInteger odds1 = getOdds(6,6).multiply(getOdds(1,1));
BigInteger odds2 = getOdds(6,6).multiply(getOdds(15,1));
BigInteger odds3 = getOdds(6,5).multiply(getOdds(27,1)).multiply(getOdds(1,1));
BigInteger odds4 = getOdds(6,5).multiply(getOdds(27,1)).multiply(getOdds(15,1)).add(getOdds(6,4).multiply(getOdds(27,2)).multiply(getOdds(1,1)));
BigInteger odds5 = getOdds(6,4).multiply(getOdds(27,2)).multiply(getOdds(15,1)).add(getOdds(6,3).multiply(getOdds(27,3)).multiply(getOdds(1,1)));
BigInteger odds6 = getOdds(6,2).multiply(getOdds(27,4)).multiply(getOdds(1,1)).add(getOdds(6,1).multiply(getOdds(27,5)).multiply(getOdds(1,1))).add(getOdds(27,6).multiply(getOdds(1,1)));
BigInteger odds1_7 = odds1.add(odds2).add(odds3).add(odds4).add(odds5).add(odds6);
BigInteger odds7 = allOdds.add(odds1_7.negate());
String odds11 = BigDecimal.valueOf(odds1.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),8,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds21 = BigDecimal.valueOf(odds2.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),8,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds31 = BigDecimal.valueOf(odds3.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),8,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds41 = BigDecimal.valueOf(odds4.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),4,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds51 = BigDecimal.valueOf(odds5.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),4,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds61 = BigDecimal.valueOf(odds6.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),4,BigDecimal.ROUND_HALF_EVEN).toPlainString();
String odds71 = BigDecimal.valueOf(odds7.longValue()).pide(BigDecimal.valueOf(allOdds.longValue()),4,BigDecimal.ROUND_HALF_EVEN).toPlainString();
double check=(new Double(odds11))+(new Double(odds21))+(new Double(odds31))+(new Double(odds41))+(new Double(odds51))+(new Double(odds61))+(new Double(odds71));
System.out.println(“一等獎（中6+1）中獎概率：”+odds1+”/”+allOdds+”=”+odds11);
System.out.println(“二等獎（中6+0）：”+odds2+”/”+allOdds+”=”+odds21);
System.out.println(“三等獎（中5+1）(3000元）中獎概率：”+odds3+”/”+allOdds+”=”+odds31);
System.out.println(“四等獎（中5+0或4+1）(200元）中獎概率：”+odds4+”/”+allOdds+”=”+odds41);
System.out.println(“五等獎（中4+0或3+1）(10元）中獎概率：”+odds5+”/”+allOdds+”=”+odds51);
System.out.println(“六等獎（中2+1或1+1或0+1）(5元）中獎概率：”+odds6+”/”+allOdds+”=”+odds61);
System.out.println(“不中獎概率：”+odds7+”/”+allOdds+”=”+odds71);
System.out.println(“驗證結果，概率相加之和為”+check);
}
private static BigInteger getOdds(Integer n,Integer k) {
BigInteger lotteryOdds = BigInteger.valueOf(1);
for(int i = 1; i<=k;i++) {
lotteryOdds = lotteryOdds.multiply(BigInteger.valueOf(n-i+1)).pide(BigInteger.valueOf(i));
}
return lotteryOdds;
}
}
結果：
run：
雙色球中獎概率（6/33+1/16）：
一等獎（中6+1）中獎概率：1/17721088=0.00000006
二等獎（中6+0）：15/17721088=0.00000085
三等獎（中5+1）(3000元）中獎概率：162/17721088=0.00000914
四等獎（中5+0或4+1）(200元）中獎概率：7695/17721088=0.0004
五等獎（中4+0或3+1）(10元）中獎概率：137475/17721088=0.0078
六等獎（中2+1或1+1或0+1）(5元）中獎概率：1043640/17721088=0.0589
不中獎概率：16532100/17721088=0.9329
驗證結果，概率相加之和為1.00001005
成功生成（總時間：0 秒）
祝大傢中大獎，交好運！
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