LeetCode 算法题 – Replace Words

首先介绍几个概念 rootsuccessorroot 后面拼接一个单词可以形成一个长单词,该长单词被称为 successor。举个例子, rootan, 拼接单词 other 形成 anotheranother 就是 successor

现在给出一个包含多个 root 的字典数组和一个句子。请将句子中的 successor 替换成 root。 如果 successor 有多个 root, 则用最短的 root 替换。


In English, we have a concept called root, which can be followed by some other words to form another longer word - let’s call this word successor. For example, the root an, followed by other, which can form another word another.

Now, given a dictionary consisting of many roots and a sentence. You need to replace all the successor in the sentence with the root forming it. If a successor has many roots can form it, replace it with the root with the shortest length.

You need to output the sentence after the replacement.

Example 1:

Input: dict = ["cat", "bat", "rat"]
sentence = "the cattle was rattled by the battery"
Output: "the cat was rat by the bat"


  • The input will only have lower-case letters
  • 1 <= dict words number <= 1000
  • 1 <= sentence words number <= 1000
  • 1 <= root length <= 100
  • 1 <= sentence words length <= 1000


如题所述,目的是将句子中的单词(也就是 successor)用其 root 替换。

  1. 根据空格将句子分离为一个单词数组
  2. 将单词逐个寻找其 root,有则替换,无则忽略
  3. 将替换后的单词数组,用空格拼接成新句子返回

另外需要注意的是,要找到最短的 root 进行替换。


func replaceWords(dict []string, sentence string) string {
    words := strings.Split(sentence, " ")

    for i := 0; i < len(words); i++ {
        for _, v := range dict {
            if len(words[i]) >= len(v) && words[i][:len(v)] == v {
                // in order to find the shortest root, doesn't break on here
                words[i] = v

    return strings.Join(words, " ")