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class Trie {
private:
    bool end;
    Trie* children[26];
public:
    /** Initialize your data structure here. */
    Trie() {
        end = false;
        memset(children, NULL, sizeof children);
    }

    /** Inserts a word into the trie. */
    void insert(string word) {
        Trie *node = this;
        for(char c: word){
            c -= 'a';
            if(!node->children[c])
                node->children[c] = new Trie();
            node = node->children[c];
        }
        node->end = true;
    }

    /** Returns if the word is in the trie. */
    bool search(string word) {
        Trie *node = this;
        for(char c: word){
            c -= 'a';
            if(!node->children[c])
                return false;
            node = node->children[c];
        }
        return node->end;
    }

    /** Returns if there is any word in the trie that starts with the given prefix. */
    bool startsWith(string prefix) {
        Trie *node = this;
        for(char c: prefix){
            c -= 'a';
            if(!node->children[c])
                return false;
            node = node->children[c];
        }
        return true;
    }
};

/**
 * Your Trie object will be instantiated and called as such:
 * Trie* obj = new Trie();
 * obj->insert(word);
 * bool param_2 = obj->search(word);
 * bool param_3 = obj->startsWith(prefix);
 */