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本文主要记录一下leetcode之单词替换
题目
代码语言：javascript复制在英语中，我们有一个叫做 词根(root)的概念，它可以跟着其他一些词组成另一个较长的单词——我们称这个词为 继承词(successor)。例如，词根an，跟随着单词 other(其他)，可以形成新的单词 another(另一个)。
现在，给定一个由许多词根组成的词典和一个句子。你需要将句子中的所有继承词用词根替换掉。如果继承词有许多可以形成它的词根，则用最短的词根替换它。
你需要输出替换之后的句子。
示例 1：
输入：dictionary = ["cat","bat","rat"], sentence = "the cattle was rattled by the battery"
输出："the cat was rat by the bat"
示例 2：
输入：dictionary = ["a","b","c"], sentence = "aadsfasf absbs bbab cadsfafs"
输出："a a b c"
示例 3：
输入：dictionary = ["a", "aa", "aaa", "aaaa"], sentence = "a aa a aaaa aaa aaa aaa aaaaaa bbb baba ababa"
输出："a a a a a a a a bbb baba a"
示例 4：
输入：dictionary = ["catt","cat","bat","rat"], sentence = "the cattle was rattled by the battery"
输出："the cat was rat by the bat"
示例 5：
输入：dictionary = ["ac","ab"], sentence = "it is abnormal that this solution is accepted"
输出："it is ab that this solution is ac"
提示：
1 <= dictionary.length <= 1000
1 <= dictionary[i].length <= 100
dictionary[i] 仅由小写字母组成。
1 <= sentence.length <= 10^6
sentence 仅由小写字母和空格组成。
sentence 中单词的总量在范围 [1, 1000] 内。
sentence 中每个单词的长度在范围 [1, 1000] 内。
sentence 中单词之间由一个空格隔开。
sentence 没有前导或尾随空格。
来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/replace-words
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。
题解
代码语言：javascript复制class Solution {
public String replaceWords(List<String> dictionary, String sentence) {
String[] words = sentence.split("\s ");
for (int i = 0; i < words.length; i ) {
for (String dic : dictionary) {
if (words[i].startsWith(dic)) {
words[i] = dic;
}
}
}
return Arrays.asList(words)
.stream()
.collect(Collectors.joining(" "));
}
}
小结
这里用双层循环使用startsWith来判断是否命中词根，如果是则替换，如果前面命中的词根不是最短的，则后面遇到会被替换掉，最后再将替换后的words数组拼接为sentence。
doc
- 单词替换
