a
ab
abaca
abache
abachi
abacista
abaciste
abacisti
abaco
...

#include <iostream>
#include <fstream>
#include <string>
using namespace std;
 
int main(void) {
	string key;
	string current_word;
	ifstream dictionary("Italiano.list");
	cout << "Quale parola si vuole cercare?" << endl; // asks for a key
	cin >> key;
	cout << "La parola che si sta cercando e' la seguente: " << key << endl; // prints the key to checkif it's typed correctly
	if(!dictionary.is_open()) {
		cout << "Errore. Impossibile accedere al dizionario." << endl; // exits with error for not being able to open the dictionary
		return 1;
	}
	while(!dictionary.eof()) {
		getline(dictionary, current_word); // stores the current line of the dic in the current_word string...
		if(current_word==key) { // ... and then compares it with the user input
			cout << current_word << endl;
			cout << "La parola " << current_word << " e' uguale alla parola cercata." << endl; /* line 21: I wanted it to print the string stored in current_word in the case of matching with the user input for another check but it prints actually only " " e' uguale alla parola cercata." << endl; " ! Don't know why, because in the previous line it prints correctly the string current_word... */
			cout << "La parola cercata e' presente nel dizionario." << endl; // tells that the word searched for has been found in the dictionary
			dictionary.close();
			return 0;
		}
	}
	dictionary.close();
	cout << "La parola cercata non e' presente nel dizionario." << endl; // tells that the word searched for has not been found in the dictionary.
	return 0;
}