<p>给定字典中的两个词,长度相等。写一个方法,把一个词转换成另一个词, 但是一次只能改变一个字符。每一步得到的新词都必须能在字典中找到。</p> <p>编写一个程序,返回一个可能的转换序列。如有多个可能的转换序列,你可以返回任何一个。</p> <p><strong>示例 1:</strong></p> <pre><strong>输入:</strong> beginWord = "hit", endWord = "cog", wordList = ["hot","dot","dog","lot","log","cog"] <strong>输出:</strong> ["hit","hot","dot","lot","log","cog"] </pre> <p><strong>示例 2:</strong></p> <pre><strong>输入:</strong> beginWord = "hit" endWord = "cog" wordList = ["hot","dot","dog","lot","log"] <strong>输出: </strong>[] <strong>解释:</strong> <em>endWord</em> "cog" 不在字典中,所以不存在符合要求的转换序列。</pre>