example39.cpp

#include <iostream>
#include <fstream>

using namespace std;

int getWhatTheyWant();
void displayItems(int x);

// main function 
int main()
{
    int whatTheyWant;

    whatTheyWant = getWhatTheyWant();

    while(whatTheyWant != 4){
        switch(whatTheyWant)
        {
            case 1:
                displayItems(1);
                break;
            case 2:
                displayItems(2);
                break;
            case 3:
                displayItems(3);
                break;
        }
    }
}

//getWhatTheyWant function 
int getWhatTheyWant()
{
    int choice;

    cout << "1 - just plain items" << endl;
    cout << "2 - helpful items" << endl;
    cout << "3 - harmful items" << endl;
    cout << "4 - quit program" << endl; 

    cin >> choice;
    return choice;
}

//display items functoin
void displayItems(int x){

    ifstream objectFile("objects.txt");
    string name;
    double power;

    if (x == 1){
        while(objectFile >> name >> power)
        {
            if(power == 0)
            {
                cout << name << ' ' << endl;
            }
        }
    }

    if (x == 2){
        while(objectFile >> name >> power)
        {
            if(power > 0)
            {
                cout << name <<  ' ' << endl;
            }
        }
    }

    if (x == 3){
        while(objectFile >> name >> power)
        {
            if (power < 0)
            {
                cout << name << ' ' << endl;
            }
        }
    }
}