vehicle maintenance program question

[djgonzo]

the following is a console vehicle maintenance program. We cannot seem to get the edit function working correctly: when we wish to delete a vehicle it does not work. Try out the program and see if it works for you. I would appreciate any advice...thanx in advanx

//============================================================================
// Vehicle Maintenance Tracking Application
// -----------------------------------------
//
// Application Overview:
// This application allows the user to input up to 20 different vehicles that will be tracked.
// Each Vehicle will have the data entered.......
//
//

//==============================================================================

// Header Files
#include "stdafx.h"
#include <iostream>
#include <string>
#include <iomanip>

// Namespace
using namespace std;

// Structs
struct vehicleType
{
	int number;
	int mileage;
	string plate;
	string vin;
	string model;
};

// Prototypes
void mainMenu(int& parUserChoice);
void initVehicles(vehicleType parVehicles[]);
void QuickCheck(vehicleType parVehicles[]);
void addVehicle(vehicleType parVehicles[]);
void EditVehicle(vehicleType parVehicles[]);
void ListVehicles(vehicleType parVehicles[]);

// Global Variables
char x;
int main (void)
{
	// Local Variable Declaration
	int userChoice = 0; // User main menu selection
	vehicleType vehicles[20]; // Create 20 element struct
	
	initVehicles(vehicles);
	do
	{
		mainMenu(userChoice);
		switch (userChoice)
		{
		case 0:
			//Exit
			break;
		case 1:
			addVehicle(vehicles);
			break;
		case 2:
			EditVehicle(vehicles); //call EditVehicle function
			break;
		case 3:
			QuickCheck(vehicles);//call QuickCheck function
			break;
		case 4:
			ListVehicles(vehicles); //call Reports function
			system("PAUSE");
			break;
		}
	}while (userChoice != 0);
}

void mainMenu(int& parUserChoice)
{ // Begin mainMenu
	do  // Displays menu until user chooses to quit the program
	{	// Begin do loop
		// Clear Screen
		system("cls");

		// List Main Menu
		cout << " Main Menu" << endl;
		cout << "===========" << endl;
		cout << "1 - Enter New" << endl;
		cout << "2 - Edit" << endl;
		cout << "3 - Quick Check" << endl;
		cout << "4 - Display Report" << endl;
		cout << "0 - Exit" << endl;
		cout << "Enter your selection(1-4, 0 to exit): ";
		cin >> parUserChoice;
	} while (parUserChoice > 4 || parUserChoice <0); // Continues until user enters a valid selection
} // End mainMenu

void addVehicle(vehicleType parVehicles[])
{	// Begin addVehicle
	bool found = false;

	for (int counter = 0;counter<20;counter++) // Loop to count through vehicle records
	{
		if (parVehicles[counter].number == 0) // Checks whether data record exists
		{
			parVehicles[counter].number = counter + 1;
			cout << "Enter Model: ";
			cin >> parVehicles[counter].model;
			cout << "Enter VIN: ";
			cin >> parVehicles[counter].vin;
			cout << "Enter Plate Number: ";
			cin >> parVehicles[counter].plate;
			cout << "Enter Mileage (Whole numbers only): ";
			cin >> parVehicles[counter].mileage;
			

		    counter = 20;
			found = true;
		}
	}

	if (!found) // Used if all struct elements have data in them
	{
		cout << "Vehicle capacity is full" << endl;
		system("pause");
	}
}


void initVehicles(vehicleType parVehicles[])
{
	// Init all vehicle numbers to 0
	for (int counter = 0;counter < 20;counter++)
	{
		parVehicles[counter].number=0;
	}
}

void EditVehicle(vehicleType parVehicles[])
{	// Begin EditVehicle()
	int EditSelect = 0;	// User selection of which vehicle attribute to edit
	int VehicleSelect = 0; // User selection of which vehicle to edit

	if(parVehicles[0].number == 0) // Checks to see if there is at least one record in the system
	{
		cout << "There are no vehicles in the database to edit.";
		system("PAUSE");
	}
	else // Executed if there is at least one vehicle in the system
	{
		cout << "Which vehicle would you like to edit?" << endl << endl;
		ListVehicles(parVehicles);
		cout << "Please make your selection (1-20) and hit Enter:";
		cin >> VehicleSelect;
		system("cls");
		cout << "What would you like to edit on the vehicle?" << endl;
		cout << "0 - Nothing/Exit Without Changes" << endl;
		cout << "1 - Model" << endl;
		cout << "2 - VIN" << endl;
		cout << "3 - License Plate" << endl;
		cout << "4 - Mileage" << endl;
		cout << "5 - Remove Vehicle" << endl;
		cin >> EditSelect;
		
		switch(EditSelect) // User selection of which vehicle item to edit
		{
		case 0:
			break; // Quit Edit
		case 1:
			cout << "Old Model: " << parVehicles[VehicleSelect-1].model << "\tNew Model: ";
			cin >> parVehicles[VehicleSelect-1].model;
			break;
		case 2:
			cout << "Old VIN: " << parVehicles[VehicleSelect-1].vin << "\tNew VIN: ";
			cin >> parVehicles[VehicleSelect-1].vin;
			break;
		case 3:
			cout << "Old Plate: " << parVehicles[VehicleSelect-1].plate << "\tNew Plate: ";
			cin >> parVehicles[VehicleSelect-1].plate;
			break;
		case 4:
			cout << "Old Mileage: " << parVehicles[VehicleSelect-1].mileage << "\tNew Mileage: ";
			cin >> parVehicles[VehicleSelect-1].mileage;
			break;
		case 5:
			cout << "Deleting Vehicle: " << parVehicles[VehicleSelect-1].model << " ";
			parVehicles[VehicleSelect-1].number = NULL;
			//parVehicles[VehicleSelect-1].model = " ";
			//parVehicles[VehicleSelect-1].vin = " ";
			//parVehicles[VehicleSelect-1].plate = " ";
			//parVehicles[VehicleSelect-1].mileage = 0;
			system("cls");
			ListVehicles(parVehicles);
			system("PAUSE");
			break;



		} // End switch statement
	}	// End else statement
}	// End EditVehicle()

void ListVehicles(vehicleType parVehicles[])
{
	if(parVehicles[0].number == 0)
	{
		cout << "You have not entered any vehicles in the database.";
		system("PAUSE");
	}
	else
	{
		cout << "Number\tModel\tVIN\tPlate\tMileage" << endl << endl;
		for(int a=0; a<20; a++)
		{	// Begin for loop
			if(parVehicles[a].number == 0)
			{	// Begin if statement
				cout << a+1 << "\tEmpty Record" << endl;	// Prints "Empty Record if a structure element does not contain info
			}	// End if statement
			else // Executes if there is at least one vehicle record in the system
			{	// Begin else statement
				cout << parVehicles[a].number;
				cout << "\t" << parVehicles[a].model;
				cout << "\t" << parVehicles[a].vin;
				cout << "\t" << parVehicles[a].plate;
				cout << "\t" << parVehicles[a].mileage << endl;
			}	// End else statement
		}	// End for loop
	}	// End else statement
}	// End ListVehicles function

void QuickCheck(vehicleType parVehicles[])
{
	
	int a = 0;
	int status = 0;
		cout << "Which vehicle would you like to check?" << endl << endl;
		ListVehicles(parVehicles);
		cout << "Please make your selection (1-20) and hit Enter:";
		cin >> a;
		a = a -1;
		system("cls");

if((parVehicles[a].mileage >= 45000) && (parVehicles[a].mileage < 50000))
{
cout << "Your vehicle will require a 50,000 mile checkup soon.\n";
status = 1;
}
else if (parVehicles[a].mileage >=50000) 
{
cout << "The vehicle you have selected is due for a 50,000 mile checkup.\n";
status = 1;
}
  
if((parVehicles[a].mileage >= 25000) && (parVehicles[a].mileage < 30000))
{
cout << "Your vehicle will require a new air filter soon.\n";
status = 1;
}
else if (parVehicles[a].mileage >=30000) 
{
cout << "The vehicle you have selected is due for a new air filter.\n";
status = 1;
}

if((parVehicles[a].mileage >= 70000) && (parVehicles[a].mileage < 75000))
{
cout << "Your vehicle will require a 50,000 mile checkup soon.\n";
status = 1;
}
else if (parVehicles[a].mileage >=75000) 
{
cout << "The vehicle you have selected is due for transmission checkup.\n";
status = 1;
}

if (status == 0)
   cout << "Your vehicle is currently up to date with maintenance.\n";

system("PAUSE");
}

[Notsosuperhero]

What does it say when you try to delete the vehicle?

If I enter 1 vehicle into it, and then delete that then it states that there are no vehicles in the database, which it should I assume. When I enter 2 or more, it deletes them and they don't appear in the databases anymore, which I assume it should do also.