2014-05-11 23:57
原题：
9 identical balls. one ball is heavy. find the heavy ball with only 2 measurements ........ dead easy.
题目：9个看起来一样的球，其中有一个偏重。给定一个不能给出具体重量，但可以比较轻重的天平，称2次找出那个重球。
解法：9个球三等分，称一次找出包含重球的那三个。3个球三等分，称一次找出重球。
代码：
1 // http://www.careercup.com/question?id=5204967652589568 2 Answer: 3 Split the 9 balls into three groups of 3 balls. 4 Choose two groups and weigh them on the balance: 5 If balanced, the heavy ball is in the other group. 6 If imbalanced, the heavy ball is in the heavier group. 7 Find the group with the heavy ball, pick two balls from the three and weigh them: 8 If balanced, the heavy ball is the other one. 9 If imbalanced, the heavy ball is the heavier one.