在英语中，我们有一个叫做 词根(root) 的概念，可以词根后面添加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 dictionary 和一个用空格分隔单词形成的句子 sentence。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"
提示：
1 <= dictionary.length <= 10001 <= dictionary[i].length <= 100dictionary[i]仅由小写字母组成。1 <= sentence.length <= 10^6sentence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。
方法一：哈希表
方法一：前缀树
class Solution:
def replaceWords(self, dictionary: List[str], sentence: str) -> str:
s = set(dictionary)
words = sentence.split()
for i, word in enumerate(words):
for j in range(1, len(word) + 1):
if word[:j] in s:
words[i] = word[:j]
break
return ' '.join(words)class Trie:
def __init__(self):
self.children = [None] * 26
self.root = None
class Solution:
def replaceWords(self, dictionary: List[str], sentence: str) -> str:
trie = Trie()
for root in dictionary:
cur = trie
for c in root:
idx = ord(c) - ord("a")
if cur.children[idx] is None:
cur.children[idx] = Trie()
cur = cur.children[idx]
cur.root = root
ans = []
for word in sentence.split():
cur = trie
for c in word:
idx = ord(c) - ord("a")
if cur.children[idx] is None or cur.root:
break
cur = cur.children[idx]
ans.append(cur.root or word)
return " ".join(ans)class Solution {
public String replaceWords(List<String> dictionary, String sentence) {
Set<String> s = new HashSet<>(dictionary);
String[] words = sentence.split(" ");
for (int i = 0; i < words.length; ++i) {
String word = words[i];
for (int j = 1; j <= word.length(); ++j) {
String t = word.substring(0, j);
if (s.contains(t)) {
words[i] = t;
break;
}
}
}
return String.join(" ", words);
}
}class Trie {
Trie[] children = new Trie[26];
String root;
}
class Solution {
public String replaceWords(List<String> dictionary, String sentence) {
Trie trie = new Trie();
for (String root : dictionary) {
Trie cur = trie;
for (char c : root.toCharArray()) {
c -= 'a';
if (cur.children[c] == null) {
cur.children[c] = new Trie();
}
cur = cur.children[c];
}
cur.root = root;
}
List<String> ans = new ArrayList<>();
for (String word : sentence.split(" ")) {
Trie cur = trie;
for (char c : word.toCharArray()) {
c -= 'a';
if (cur.children[c] == null || cur.root != null) {
break;
}
cur = cur.children[c];
}
ans.add(cur.root == null ? word : cur.root);
}
return String.join(" ", ans);
}
}class Solution {
public:
string replaceWords(vector<string>& dictionary, string sentence) {
unordered_set<string> s(dictionary.begin(), dictionary.end());
istringstream is(sentence);
vector<string> words;
string ss;
while (is >> ss) words.push_back(ss);
for (int i = 0; i < words.size(); ++i)
{
string word = words[i];
for (int j = 1; j <= word.size(); ++j)
{
string t = word.substr(0, j);
if (s.count(t))
{
words[i] = t;
break;
}
}
}
string ans = "";
for (string& word : words) ans += word + " ";
ans.pop_back();
return ans;
}
};class Trie {
public:
string root;
vector<Trie*> children;
Trie() {
root = "";
children.resize(26);
}
};
class Solution {
public:
string replaceWords(vector<string>& dictionary, string sentence) {
Trie* trie = new Trie();
for (auto root : dictionary)
{
Trie* cur = trie;
for (char c : root)
{
if (!cur->children[c - 'a']) cur->children[c - 'a'] = new Trie();
cur = cur->children[c - 'a'];
}
cur->root = root;
}
string ans = "";
istringstream is(sentence);
vector<string> ss;
string s;
while (is >> s) ss.push_back(s);
for (auto word : ss)
{
Trie* cur = trie;
for (char c : word)
{
if (!cur->children[c - 'a'] || cur->root != "") break;
cur = cur->children[c - 'a'];
}
ans += cur->root == "" ? word : cur->root;
ans += " ";
}
ans.pop_back();
return ans;
}
};func replaceWords(dictionary []string, sentence string) string {
s := map[string]bool{}
for _, v := range dictionary {
s[v] = true
}
words := strings.Split(sentence, " ")
for i, word := range words {
for j := 1; j <= len(word); j++ {
t := word[:j]
if s[t] {
words[i] = t
break
}
}
}
return strings.Join(words, " ")
}func replaceWords(dictionary []string, sentence string) string {
trie := &Trie{}
for _, root := range dictionary {
cur := trie
for _, c := range root {
c -= 'a'
if cur.children[c] == nil {
cur.children[c] = &Trie{}
}
cur = cur.children[c]
}
cur.root = root
}
var ans []string
for _, word := range strings.Split(sentence, " ") {
cur := trie
for _, c := range word {
c -= 'a'
if cur.children[c] == nil || cur.root != "" {
break
}
cur = cur.children[c]
}
if cur.root == "" {
ans = append(ans, word)
} else {
ans = append(ans, cur.root)
}
}
return strings.Join(ans, " ")
}
type Trie struct {
children [26]*Trie
root string
}