leetcode 日经贴，Cpp code -Implement Trie (Prefix Tree)

Implement Trie (Prefix Tree)

class TrieNode {
private:
    TrieNode *next[26];
    bool ed;
public:
    // Initialize your data structure here.
    TrieNode() {
        memset(next, 0, sizeof(TrieNode *) * 26);
        ed = false;
    }
    TrieNode *insert(char ch) {
        int p = ch - 'a';
        return next[p] = new TrieNode();
    }
    TrieNode *get(char ch) {
        int p = ch - 'a';
        return next[p];
    }
    void seted(bool val) {
        ed = val;
    }
    bool geted() {
        return ed;
    }
};

class Trie {
public:
    Trie() {
        root = new TrieNode();
    }

    // Inserts a word into the trie.
    void insert(string s) {
        TrieNode *r = root;
        for (int i = 0; i < s.length(); ++i) {
            TrieNode *p = r->get(s[i]);
            if (!p) {
                p = r->insert(s[i]);
            }
            r = p;
        }
        r->seted(true);
    }

    // Returns if the word is in the trie.
    bool search(string key) {
        TrieNode *r = root;
        for (int i = 0; i < key.length(); ++i) {
            r = r->get(key[i]);
            if (!r) return false;
        }
        return r->geted();
    }

    // Returns if there is any word in the trie
    // that starts with the given prefix.
    bool startsWith(string prefix) {
        TrieNode *r = root;
        for (int i = 0; i < prefix.length(); ++i) {
            r = r->get(prefix[i]);
            if (!r) return false;
        }
        return true;
    }

private:
    TrieNode* root;
};

// Your Trie object will be instantiated and called as such:
// Trie trie;
// trie.insert("somestring");
// trie.search("key");