Database problems in C++ - c++

Question

I have been messing with this program for past 8 hours and I do not know where to go further. I am very sorry that my code is in a foreign language, I tried to comment it in English to my best efforts.
I managed to debug it at last.but I have few problems.
1)How to print the first 5 lines(the first 5 lines from the txt fail) and then the previous 5 again?My rather pathetic try is listed below.Example:
At first you have Memento , Godfather. You print the next five
Godfather II , Shawshank Redemption, Leon, A Bittersweet Life,Se7en.Now previous 5:Memento, Godfather,Godfather II, Shawshank Redemption, Leon
2) How to use characters rather than numbers to make a menu in the program?
3)Am I really stupid? Answer honestly, please.
I will take a break now and get some sleep, will go through the replies in the morning, I hope it isnt aganist the rules.
#include <iostream>
#include <string>
#include <fstream>
using namespace std;
void sisend(); /*input*/
string valik(); /*choice*/
void kogukuvand(); /* the whole display of the database */
void valjumine(); /* program quit*/
void sisendvoivaljumine(); /*quiting with output to file or not*/
void viisjuurde(); /* input further 5 lines from the file */
void viismaha(); /* input previous 5 lines from the file*/
int main()
{
system ("title Filmide andmebaas"); /*Movie database*/
system ("cls");
int valik;
cout << "Vajuta klahv 'j',kui tahad naha jargmist 5 kirjet."<< endl; /* j to get extra 5*/
cout << "Vajuta klahv 'e',kui tahad naha eelmist 5 kirjet."<< endl; /* e for previous 5 lines */
cout << "Vajuta klahv 'v',kui tahad lopetada programmi taitumist."<< endl; /* v for the output */
cin >> valik;
switch (valik) { /*choice*/
case 1:
viisjuurde();
break;
case 2:
viismaha();
break;
case 3:
sisendvoivaljumine();
break;
}
}
void viisjuurde()
{
ifstream filmike("andmebaas.txt");
int n, sum = 5;
while (filmike >> n) {
sum += n;
string film;
string vaadatud;
int aasta;
long int hinne;
system ("CLS");
cout << "Kogu filmide andmebaas"<<endl;
cout << "Film" << " " << "Aasta" << " " <<"Hinne"<< " " << "Vaadatud" << endl;
cout << "------------------------------" << endl;
while (filmike>> film >> aasta >> hinne >> vaadatud)
{
cout << film << " " << aasta << " " << hinne << " " << vaadatud << endl;
}
system ("pause");
cin.get();
main();
}
}
void viismaha()
{
ifstream filmike("andmebaas.txt");
int n, sum = -5;
while (filmike >> n) {
sum += n;
}
string film;
string vaadatud;
int aasta;
long int hinne;
system ("CLS");
cout << "Kogu filmide andmebaas"<<endl;
cout << "Film" << " " << "Aasta" << " " <<"Hinne"<< " " << "Vaadatud" << endl;
cout << "------------------------------" << endl;
while (filmike>> film >> aasta >> hinne >> vaadatud)
{
cout << film << " " << aasta << " " << hinne << " " << vaadatud << endl;
}
system ("pause");
cin.get();
main();
}
void sisend() /* user input */
{
string nimi;
int aasta;
long int hinne;
string vaadatud;
ofstream lisafilm("andmebaas.txt", ios::app);
cout <<"Sisestage filmi nimi." << endl; /*Enter film's name */
cin >> nimi;
string film;
cout << "Sisestage filmi ilmumisaasta." << endl; /* Enter film's year */
cin >> aasta;
cout << "Sisestage filmi hinne." << endl; /* Enter film's rating */
cin >> hinne;
cout << "Kas olete filmi juba vaadanud?" << endl; /* Has the user seen the movie already*/
cout << "Vastake 'Jah' voi 'Ei'" << endl;
cin >> vaadatud;
cout << film << " " << aasta << " " << hinne << " " << vaadatud << endl;
lisafilm<< nimi << " " << aasta << " " << hinne<< " " << vaadatud << endl;
lisafilm.close();
main();
cout << "Aitah kasutamast andmebaasi." << endl;
system("pause");
cin.get ();
}
void valjumine() /*quiting without output */
{
system("CLS");
cout << "Aitah kasutamast andmebaasi." << endl;
system("pause");
cin.get ();
}
void kogukuvand() /* the whole movie database*/
{
ifstream filmike("andmebaas.txt");
string film;
string vaadatud;
int aasta;
long int hinne;
system ("CLS");
cout << "Kogu filmide andmebaas"<<endl;
cout << "Film" << " " << "Aasta" << " " <<"Hinne"<< " " << "Vaadatud" << endl;
cout << "------------------------------" << endl;
while (filmike>> film >> aasta >> hinne >> vaadatud)
{
cout << film << " " << aasta << " " << hinne << " " << vaadatud << endl;
}
system ("pause");
cin.get();
main();
}
void sisendvoivaljumine()
{
int valik2;
system ("CLS");
cout << "Vajuta klahv 'j',kui tahad salvestada kirje ja v2ljuda programmist." << endl; /* output new movie to file and quit*/
cout << "Vajuta klahv 'e',kui ei taha salvestada kirje ja v2ljuda programmist." << endl; /*just quit, without any output to file*/
cout << "Vajuta klahv 'k',kui tahad naha kogu filmide andmebaasi." << endl; /* display the whole movie database*/
cin >> valik2;
switch (valik2)
{
case 1:
sisendvoivaljumine();
break;
sisend();
break;
case 2:
valjumine();
break;
case 3:
kogukuvand();
break;
}
}

Answer 1

Some hints:
Indent and format your code according to common convention. It makes it easer for you to read and debug (and everyone else too).
You are calling main() recursively. Do not do that. Use a loop around you menu switch instead.
A good failsafe way of reading lines from files is by using getline(). Combine with an istringstream to read individual values from the line:
ifstream infile("somefile.txt");
string line;
while ( getline(infile, line) ) // read infile until eof
{
istringstream iss(line); // create stream from line data
string a, b, c, d;
iss >> a >> b >> c >> d; // read just as from cin
cout << a << "," << b << "," << c << "," << d << endl;
}
If you read to integers you need to verify that the read succeeded (unless you are sure the file contained digits at the point you where reading):
int n;
if (iss >> n)
{
// read OK
}
else
{
// read failed
infile.clear();
string junk;
infile >> junk;
cout << "ERROR: bad data was:" << junk << endl;
}
To use characters in menu you can use char datatype. It's a good idea, since char input won't fail:
char choice;
cin >> choice;
switch (choice)
{
case '1':
{
// do something
break;
}
case 'A':
{
// do something
break;
}
}
Beware that sisendvoivaljumine calls itself recursively when you select that option. As menus can be selected over and over again, infinitely, you are better off by using a loop to repeat the menu.
You want to read up on the above topics. Check http://www.cplusplus.com.
When you debug, make sure you know exactly which lines the program is executing at each point. Add clear debug output to help you.