Printing from Trie - c++

Question

I have built a trie in C++ designed to hold words of sentences. Each sentence will have a weight which determines the order in which they should be output. I have several recursive functions that call other recursive functions, and the dilemma I am facing is that I want to print my list only once.
Basically my get function calls the printFromNode function which creates the vector of pairs p that I want to sort and print. If someone could point me in the right direction in how to do that it would be much appreciated.
Code:
Trie.cpp:
//#include "Trie.h"
#include <iostream>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>
#include <sstream>
#include <stack>
using namespace std;
class Node
{
private:
string word = "";
bool endOfSentence = false;
int weight = -1;
public:
vector<Node> children = {};
Node() {
this->setWord("");
}
Node(string s){
this->setWord(s);
}
string getWord(){
return this->word;
}
void setWord(string s) {
this->word = s;
}
void setEOS(){
this->endOfSentence = true;
}
void setWeight(int weight){
this->weight = weight;
}
int getWeight() {
return this->weight;
}
};
class Trie
{
public:
Node root;
void add(vector<string> phrase, int weight, Node* n){
Node* current = n;
int w = weight;
int found = -1;
for (int i = 0; i < current->children.size(); i++) {
if (phrase[0] == current->children[i].getWord()) {
found = i;
}
}
if (found > -1) {
current = &current->children[found];
phrase.erase(phrase.begin());
add(phrase, w, current);
}
else {
addPhrase(phrase, w, current);
}
}
void addPhrase(vector<string> phrase, int weight, Node* n) {
Node* current = n;
for (int i = 0; i < phrase.size(); i++) {
Node temp = *new Node(phrase[i]);
current->children.push_back(temp);
current = &current->children.back();
if (i == phrase.size() - 1) {
current->setEOS();
current->setWeight(weight);
}
}
}
void get(vector<string> search) {
Node* current = &this->root;
get(search, current);
}
void get(vector<string> search, Node* n) {
Node* current = n;
int found = -1;
//test search size
if (search.size() == 0) {
cout << "Please enter a valid search" << endl;
}
for (int i = 0; i < current->children.size(); i++) {
if (search[0] == current->children[i].getWord()) {
found = i;
}
}
if (found > -1 && search.size() == 1) {
current = &current->children[found];
printFromNode(*current);
maxNode(*current);
}
else if (found > -1 && search.size() != 1) {
current = &current->children[found];
search.erase(search.begin());
get(search, current);
}
else {
cout << "Not Found" << endl;
}
}
void printOutput(vector<pair<int,string>> p){
sort(p.begin(), p.end());
cout << p.size() << endl;
for (int i = 0; i < p.size(); i++) {
cout << p[i].second << " " << endl;
}
}
void printFromNode(Node n) {
vector<string> phrase = {};
vector <pair < int, string>> final = {};
printFromNode(n,phrase,final);
}
void printFromNode(Node n, vector<string> &v, vector<pair<int,string>> &p) {
string output;
if (n.getWord() == "") {
return;
}
for (int i = 0; i < n.children.size(); i++) {
if (n.children[i].getWeight() > 0) {
for (int i = 0; i < v.size(); i++)
{
output.append(v[i] + " ");
}
output.append(n.children[i].getWord());
p.push_back(make_pair(n.children[i].getWeight(), output));
}
v.push_back(n.children[i].getWord());
printFromNode(n.children[i], v, p);
v.pop_back();
sort(p.begin(), p.end());
}
return;
}
void maxNode(Node n) {
int max = 0;
int index = 0;
int temp = 0;
for (int i = 0; i < n.children.size(); i++) {
temp = n.children[i].children.size();
if (temp > max) {
max = temp;
index = i;
}
}
cout << n.children[index].getWord() << " " << max << endl;
}
};
Main.cpp:
#include "Trie.cpp"
#include <iostream>
#include <sstream>
#include <string>
#include <vector>
using namespace std;
int main(int argc, char* argv[]) {
// Initialize trie up here
Trie myTrie = *new Trie();
// parse input lines until I find newline
for(string line; getline(cin, line) && line.compare(""); ) {
stringstream ss(line);
string string_weight;
ss >> string_weight;
int weight = stoi(string_weight);
// I am just going to put these words into a vector
// you probably want to put them in your trie
vector<string> phrase = {};
for(string word; ss >> word;) {
phrase.push_back(word);
}
myTrie.add(phrase, weight, &myTrie.root);
vector<string> ans = {};
}
// parse query line
string query;
getline(cin, query);
stringstream ss(query);
vector<string> search = {};
for (string query; ss >> query;) {
search.push_back(query);
}
myTrie.get(search);
return 0;
}

Answer 1

You can remove recursive methods, and doing something like the following:
#include <algorithm>
#include <iostream>
#include <map>
#include <string>
#include <vector>
#include <set>
class Node
{
public:
bool endOfSentence = false;
std::set<int> weights;
std::map<std::string, Node> children;
Node() = default;
const Node* get(const std::string& word) const
{
auto it = children.find(word);
if (it == children.end()) {
return nullptr;
}
return &it->second;
}
auto find_by_weight(int weight) const
{
return std::find_if(children.begin(),
children.end(),
[=](const auto& p){ return p.second.weights.count(weight);});
}
};
class Trie
{
Node root;
public:
void add(int weight, const std::vector<std::string>& phrase)
{
Node* node = &root;
for (const auto& word : phrase) {
node->weights.insert(weight);
node = &node->children[word];
}
node->weights.insert(weight);
node->endOfSentence = true;
}
bool contains(const std::vector<std::string>& phrase) const
{
const Node* node = &root;
for (const auto& word : phrase) {
node = node->get(word);
if (node == nullptr) {
return false;
}
}
return node->endOfSentence;
}
void print(int weight) const
{
const Node* node = &root;
const char* sep = "";
while (node) {
const auto it = node->find_by_weight(weight);
if (it == node->children.end()) {
break;
}
std::cout << sep << it->first;
sep = " ";
node = &it->second;
}
std::cout << std::endl;
}
void print_all() const
{
for (int i : root.weights) {
print(i);
}
}
};
And usage/Test:
int main(int argc, char* argv[]) {
const std::vector<std::vector<std::string>> sentences = {
{"My", "name", "is", "John"},
{"My", "house", "is", "small"},
{"Hello", "world"},
{"Hello", "world", "!"}
};
Trie trie;
int i = 0;
for (const auto& sentence : sentences) {
trie.add(i, sentence);
++i;
}
const std::vector<std::vector<std::string>> queries = {
{"My", "name", "is", "John"},
{"My", "house"},
{"Hello", "world"}
};
for (const auto& query : queries) {
std::cout << trie.contains(query) << std::endl;
}
trie.print_all();
}
Demo