offer2-63

在英语中，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，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。

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。

//leetcode submit region begin(Prohibit modification and deletion)
class Solution {
    class Trie {
        Trie[] leaves;
        boolean isEnd;

        public Trie() {
            this.leaves = new Trie[26];
            this.isEnd = false;
        }

        public void addWord(String word) {
            if (word == null) {
                return;
            }
            Trie trie = this;
            for (char ch : word.toCharArray()) {
                if (trie.leaves[ch - 'a'] == null) {
                    trie.leaves[ch - 'a'] = new Trie();
                }
                trie = trie.leaves[ch - 'a'];
            }
            trie.isEnd = true;
        }

        public String findDict(String word) {
            if (word == null) {
                return null;
            }
            Trie trie = this;
            StringBuilder sb = new StringBuilder();
            for (char ch : word.toCharArray()) {
                if (trie.leaves[ch - 'a'] == null) {
                    return word;
                }
                trie = trie.leaves[ch - 'a'];
                sb.append(ch);
                if (trie.isEnd) {
                    return sb.toString();
                }
            }
            return word;
        }
    }

    public String replaceWords(List<String> dictionary, String sentence) {
        Trie trie = new Trie();
        for (String dict : dictionary) {
            trie.addWord(dict);
        }

        StringBuilder sb = new StringBuilder();
        for (String word : sentence.split(" ")) {
            sb.append(trie.findDict(word));
            sb.append(" ");
        }

        if (sb.length() > 0) {
            return sb.substring(0, sb.length() - 1);
        } else {
            return "";
        }
    }
}
//leetcode submit region end(Prohibit modification and deletion)