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四人过桥问题的SQL解法
看了开发版的帖子,又没有忍住,简单写了一个SQL语句。关于问题的详细描述可以参考http://www.itpub.net/thread-1595264-1-1.html 传说中的微软面试题: 有一群人A,B,C,D (人数>=2)要在夜里走过独木桥过河,他们只有一把手电筒。四个人的速度不同,过河分别需要1,2,5,10分钟,桥上最多走两个人,两个人一起走时按速度慢的计算。过河一定要用手电筒。请问最快的方法是如何安排,需要几分钟? 例子输出: A B,A,A C,A,A D 19 直接给出最终结果: SQL> WITH C AS 2 (SELECT NAME, TIME, POWER(2, ROWNUM – 1) POS FROM BRIDGE_CROSSING), 3 A AS 4 (SELECT 0 RN, A.NAME || ‘ ‘ || B.NAME NAME, … Continue reading