Are there any problems related to the size of a text file in c++?

Question

So I've written a program which picks a word in a list of words, masks it by switching its letters and ask the user to find the starting word in less than 5 tries. here's the main.cpp file:

#include <iostream>
#include <fstream>
#include <string>
#include <ctime>
#include <cstdlib>
#include <vector>
#include "mystere.h"
using namespace std;

int main(int argc, char const *argv[])
{
    srand(time(0));
    char again('Y');
    vector<int> scores;
    string secret(""),mystere(""),userInput("");
    do{
        int tries(0);
        secret=choixMot("dico.txt"); //The file I'm talking about is right there
        mystere=masque(secret);
        bool comparaison;
        do{
            cout << "What is this word? " << mystere << endl; //Shows the masked word to the user
            cin >> userInput;
            toUpper(userInput);
            comparaison=compare(userInput,secret);
            verification(comparaison);
            tries++;
        }while(!comparaison && tries<5);
        if(tries==5)
            cout << "Lost! the solution was: " << secret << endl;
        cout << "Wanna try again?" << endl;
        cin >> again;
        toUpper(again);
        scores.push_back(tries);
    }while(again=='Y');
    if(again=='N'){
        cout << "Average number of tries: " << moyenne(scores) << endl;
        cout << "Bye and thanks for playing." << endl;
    }
    else
        cout << "Unrecognized character, logging you out." << endl;
    return 0;
}

here's the mystere.cpp file:

#include "mystere.h"

bool compare(string const& mot1, string const& mot2){
    if(mot1.size()!=mot2.size()){
        return false;
    }else{
        for(int i(0); i<mot1.size(); i++){
            if(mot1[i]!=mot2[i]) return false;
        }
        return true;
    }
}

string masque(string secret){
    string masque;
    int indice(0);
    while(secret.size()>0){
        indice=rand()%secret.size();
        masque.push_back(secret[indice]);
        secret.erase(indice,1);

    }
    return masque;
}

void toUpper(string& chaine){
    for(int i(0);i<chaine.size();i++){
        if(chaine[i]>96 && chaine[i]<123)
            chaine[i]-=32;
    }
}

void toUpper(char& charactere){
    if(charactere>96 && charactere<123)
        charactere-=32;
}

void verification(bool comparaison){
    if(comparaison)
        cout << "Congrats! " << endl;
    else
        cout << "This is not the word" << endl;
}

double moyenne (vector<int> const& scores){
    double moyenne(0),taille(scores.size());
    for(int i(0);i<taille;i++)
        moyenne+=scores[i];
    return(moyenne/taille);
}
// Mot means "Word" in english for those wondering
string choixMot(string const nomFichier){
    string Mot("");
    int nbrMots(0),indice(0);
    ifstream fichier(nomFichier.c_str());
    if(fichier){
        //cout << fichier.tellg();
        while(getline(fichier,Mot)){
            nbrMots++;
        }
        fichier.clear(); //to clear the eof bit and allow seekg to escape from the end of the file
        fichier.seekg(0,ios::beg);
        getline(fichier,Mot);
        indice=rand()%nbrMots+1;
        for(int i(0);i<indice;i++)
            getline(fichier,Mot);
    }else
        cout << "Impossible to open the file in reading mode" << endl;
    return Mot;
}

And here is the mystere.h file:

#ifndef MYSTERE
#define MYSTERE
#include <iostream>
#include <string>
#include <ctime>
#include <cstdlib>
#include <vector>
#include <fstream>
using namespace std;
bool compare(string const& mot1, string const& mot2);

string masque(string secret);

void verification(bool comparaison);

void toUpper(string& chaine);

void toUpper(char& charactere);

double moyenne (vector<int> const& scores);

string choixMot(string const nomFichier);

#endif

finally, here is the Test.txt file:

TABLE
BATEAU
CHAUSSURES
BOUTEILLE
MONTRE
TELEPHONE
ORDINATEUR
ECOUTEURS
ECRAN
CHAISE

When I build the program replacing "dico.txt" in the main function by "Test.txt", there is no problem and the program works perfectly well. But when I use the "dico.txt" file which is accessible here and that I won't put here because it is around 30000 lines. The program builds perfectly but when it runs I see this: XAELOINHNULs word ? so the cout is not working anymore. I want to understand the problem and where it comes from as it never happens with the smaller file. Thanks a lot to those who'll take time to read and even test my program!

Answer 1

Based on the expected output

What is this word? XAELOINHNUL

And the actual output

XAELOINHNULs word ?

, my crystal ball says: you're on Linux or Mac and your TXT file is from Windows.

Why is this happening? When reading a text file with Windows line-endings (CR, LF) on POSIX systems, the CR character becomes part of the string, and when printed, the cursor is moved to the beginning of the line prior to printing.

To fix this, convert the TXT file to Unix line-endings, e.g. using dos2unix utility. Or strip \r characters from the input string in your program.