OpenJudge

H:Edit Step Ladders

总时间限制:
3000ms
内存限制:
65536kB
描述
An edit step is a transformation from one word x to another word y such that x and y are words in the dictionary, and x can be transformed to y by adding, deleting, or changing one letter. So the transformation from dig to dog or from dog to do are both edit steps. An edit step ladder is a lexicographically ordered sequence of words w1, w2, ... wn such that the transformation from wi to wi+1 is an edit step for all i from 1 to n-1.
输入
For a given dictionary, you are to compute the length of the longest edit step ladder. The input to your program consists of the dictionary - a set of lower case words in lexicographic order - one per line. No word exceeds 16 letters and there are no more than 25000 words in the dictionary.
输出
The output consists of a single integer, the number of words in the longest edit step ladder.
样例输入
cat
dig
dog
fig
fin
fine
fog
log
wine
样例输出
5
来源
Waterloo local 2000.09.23
全局题号
1566
提交次数
16
尝试人数
2
通过人数
2