Please provide assistance to fix the segmentation fault error I am receiving and solve the following problem I am working on:

My goal is to build a Trie data structure in C++ that can do the following:

1. Capable to insert any given dictionary .txt file filled with a single word per line (i.e. file includes ant, bat, car, desk, etc.) into the Trie. A sample dictionary file that I'm working with can be found at http://txt.do/1pht5
2. Prompts the user to input some prefix search and provides an autocomplete suggestion (i.e. file includes bat, bar, bass, and user inputs ba which should suggest bat, bar, bass, etc.)
3. Lastly, if the user inputs a prefix search that is not within the Trie, it will recommend the top 3 most similar entries in the Trie (i.e. user prefix input is baq which is not part of the dictionary txt file but bat, bar, bass are which should be suggested)

I have been able to write the following code so far but I'm having difficulties in fixing the segmentation error and making it run.

#include #define alphabet_size 26 using namespace std; class TrieNode { public: TrieNode* children[alphabet_size]; bool endofLeaf; TrieNode(){ for(int i = 0; i < alphabet_size; i++) children[i] = NULL; endofLeaf = false; } }; class Trie { public: TrieNode* root; Trie() {root = new TrieNode();} void Dict_insert(string word){ TrieNode* temp = root; for(int i = 0; i < word.length(); i++){ if(temp->children[word[i]-'a'] == NULL){ temp->children[word[i]-'a'] = new TrieNode(); } temp = temp->children[word[i]-'a']; } temp->endofLeaf = true; } bool search (string word){ TrieNode* tmp = root; for(int i = 0; i < word.size(); i++) { if(tmp->children[word[i]-'a'] == NULL){ return false; } tmp = tmp->children[word[i]-'a']; } return tmp; } void auto_recommendation(string word){ TrieNode* autorec = root; if(autorec->endofLeaf == true) cout << word << endl; for(int i = 0; i < alphabet_size; i++){ if(autorec->children[i] != NULL){ word.push_back((char)i); auto_recommendation(word); word.pop_back(); } } } }; int main(){ Trie* t = new Trie(); fstream dictionaryfile; dictionaryfile.open("Dictionary.txt",ios::in); if (dictionaryfile.is_open()){ string DictEntry; while(getline(dictionaryfile, DictEntry)){ t->Dict_insert(DictEntry); } dictionaryfile.close(); } string searchQuery; cout << "Type in a search: " << endl; getline(cin,searchQuery); cout << "/nDid you mean: " << endl; t->search(searchQuery); if (t->search(searchQuery) == false) /* Call a recommendation search function which recommends the top 3 most similar entries within the Trie*/ cout<<"No suggestions available. "; else t->auto_recommendation(searchQuery); return 0; }