1 人解决，8 人已尝试。
1 份提交通过，共有 37 份提交。
9.9 EMB 奖励。
单点时限: 3.0 sec
内存限制: 256 MB
A word ladder is a sequence of words, in which two consecutive words differ by exactly
one letter. An example of such a ladder (usually arranged vertically, hence the “ladder”)
would be: beer, brew, brow, word, down. Note that to get from one word to the next, the
letters may be rearranged, and exactly one letter is changed.
For this problem, you will be given a dictionary of distinct words, all of the same length.
Your task is to write a program that finds a word ladder of minimal length, such that the
first and last word of the ladder have no letters in common.
On the first line an integer t (1 <= t <= 100): the number of test cases. Then for each test
case:
1.A line with two space-separated integers n (2 <= n <= 100) and l (1 <= l <= 20): the
number of words and their length.
2.n lines with a word, each consisting of l lowercase letters (a - z).
For each testcase:
It is guaranteed that at least one such ladder can be constructed. If there is more than
one, output the one that comes first lexicographically.
Notes
If s and t are strings of equal length and si denotes the ith character of s, then s precedes
t lexicographically if for some i: si < ti and sj = tj for all j < i.
1 9 3 alt spy sea opt pea ape spa apt ale
ale alt apt opt
1 人解决，8 人已尝试。
1 份提交通过，共有 37 份提交。
9.9 EMB 奖励。