// Returns if the word is in the trie.
bool search(string key) {
TrieNode *cur = root;
for(auto ch : key) {
cur = cur->get_child(ch);
if (cur == nullptr)
return false;
}
return cur->is_end;
}
// Returns if there is any word in the trie
// that starts with the given prefix.
bool startsWith(string prefix) {
TrieNode *cur = root;
for (auto ch : prefix) {
cur = cur->get_child(ch);
if (cur == nullptr)
return false;
}
return true;
}
// Inserts a word into the trie.
void insert(string s) {
if (search(s)) return;
TrieNode* cur = root;
for (auto ch : s) {
TrieNode *child = cur->get_child(ch);
if (child)
cur = child;
else {
TrieNode *newNode = new TrieNode(ch);
cur->children.push_back(newNode);
cur = newNode;
}
++cur->num_of_shared_node; // parent node is shared
}
cur->is_end = true;
}