Error, Please help

Any one mind helping me? i'm new to this site. I'm just trying to finish this program. The only thing that i haven't gotten to work is the prompt for the record number, but everything else works. Sorry if this might be super easy for some of you guys lol.
Any help or suggestions please!


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#include "stdafx.h"
#include <iostream>
#include <fstream>
using namespace std;

int get_double(double default_value);
int get_int(int default_value);
void write_report();
void read_report();

int main()
{
	int choice;
	do {
		cout << "This is the Automotive report system. Press 1 to write. Press 2 to read. Press 0 to exit... ";
		cin >> choice;
		if (choice == 1) {
			write_report();
		}
		else if (choice == 2) {
			read_report();
		}
	} while (choice != 0);

    return 0;
}
#define COL_WIDTH 80

int get_double(double default_value) {
	char s[COL_WIDTH + 1];
	cin.getline(s, COL_WIDTH);
	if (strlen(s) == 0) {
		return default_value;
	}
	return atof(s);
}
int get_int(int default_value) {
	char s[COL_WIDTH + 1];
	cin.getline(s, COL_WIDTH);
	if (strlen(s) == 0) {
		return default_value;
	}
	return atoi(s);
}
void write_report() {
	char model[20];
	char make[20];
	char year[5];
	int mileage = 0;
	double value = 0;
	int rcn = 0;
	int recsize = sizeof(model) + sizeof(int);
	fstream automobile("automobile.data", ios::binary | ios::out);
	cout << "Enter a record number: ";
	rcn = get_int(0);
	cout << "Enter the model of the car: ";
	cin.getline(model, sizeof(model) - 1);
	cout << "Enter the make of the car: ";
	cin.getline(make, sizeof(make) - 1);
	cout << "Enter the year of the car: ";
	cin.getline(year, sizeof(year));
	cout << "Enter the mileage on the car: ";
	mileage = get_int(0);
	cout << "Enter the value of the car: ";
	value = get_double(0);
	automobile.seekp(rcn*recsize);
	automobile.write(model, sizeof(model) - 1);
	automobile.write(make, sizeof(make) - 1);
	automobile.write(year, sizeof(year) - 1);
	automobile.write((char*)(&mileage), sizeof(int));
	automobile.write((char*)(&value), sizeof(double));
	automobile.close();
}
void read_report() {
	char model[20];
	char make[20];
	char year[5];
	int mileage = 0;
	double value = 0;
	int rcn = 0;
	int recsize = sizeof(model) + sizeof(int);
	fstream automobile("automobile.data", ios::binary | ios::in);
	cout << "Enter a record number" << endl;
	rcn = get_int(0);
	automobile.seekp(rcn*recsize);
	automobile.read(model, sizeof(model) - 1);
	automobile.read(make, sizeof(make) - 1);
	automobile.read(year, sizeof(year) - 1);
	automobile.read((char*)(&mileage), sizeof(int));
	automobile.read((char*)(&value), sizeof(double));
	cout << "The model is: " << model << endl;
	cout << "The make is: " << make << endl;
	cout << "The year is: " << year << endl;
	cout << "The milage is: " << mileage << endl;
	cout << "Value of car is: " << value << endl;
	automobile.close();
}


Last edited on
I added two lines to the write function to fix the prompt. I don't know what is best practice is. This solution is from C++ Primer Plus by Stephen Prata.

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#include <iostream>
#include <fstream>
using namespace std;

int get_double(double default_value);
int get_int(int default_value);
void write_report();
void read_report();

int main()
{
	int choice;
	do {
		cout << "This is the Automotive report system. Press 1 to write. Press 2 to read. Press 0 to exit... ";
		cin >> choice;
		if (choice == 1) {
			write_report();
		}
		else if (choice == 2) {
			read_report();
		}
	} while (choice != 0);

	return 0;
}
#define COL_WIDTH 80

int get_double(double default_value) {
	char s[COL_WIDTH + 1];
	cin.getline(s, COL_WIDTH);
	if (strlen(s) == 0) {
		return default_value;
	}
	return atof(s);
}
int get_int(int default_value) {
	char s[COL_WIDTH + 1];
	cin.getline(s, COL_WIDTH);
	if (strlen(s) == 0) {
		return default_value;
	}
	return atoi(s);
}
void write_report() {
	char model[20];
	char make[20];
	char year[5];
	int mileage = 0;
	double value = 0;
	int rcn = 0;
	int recsize = sizeof(model) + sizeof(int);
	fstream automobile("automobile.data", ios::binary | ios::out);
	cout << "Enter a record number: ";
	rcn = get_int(0);
        while (cin.get() != '\n')
		continue;
	cout << "Enter the model of the car: ";
	cin.getline(model, sizeof(model) - 1);
	cout << "Enter the make of the car: ";
	cin.getline(make, sizeof(make) - 1);
	cout << "Enter the year of the car: ";
	cin.getline(year, sizeof(year));
	cout << "Enter the mileage on the car: ";
	mileage = get_int(0);
	cout << "Enter the value of the car: ";
	value = get_double(0);
	automobile.seekp(rcn*recsize);
	automobile.write(model, sizeof(model) - 1);
	automobile.write(make, sizeof(make) - 1);
	automobile.write(year, sizeof(year) - 1);
	automobile.write((char*)(&mileage), sizeof(int));
	automobile.write((char*)(&value), sizeof(double));
	automobile.close();
}
void read_report() {
	char model[20];
	char make[20];
	char year[5];
	int mileage = 0;
	double value = 0;
	int rcn = 0;
	int recsize = sizeof(model) + sizeof(int);
	fstream automobile("automobile.data", ios::binary | ios::in);
	cout << "Enter a record number" << endl;
	rcn = get_int(0);
	automobile.seekp(rcn*recsize);
	automobile.read(model, sizeof(model) - 1);
	automobile.read(make, sizeof(make) - 1);
	automobile.read(year, sizeof(year) - 1);
	automobile.read((char*)(&mileage), sizeof(int));
	automobile.read((char*)(&value), sizeof(double));
	cout << "The model is: " << model << endl;
	cout << "The make is: " << make << endl;
	cout << "The year is: " << year << endl;
	cout << "The milage is: " << mileage << endl;
	cout << "Value of car is: " << value << endl;
	automobile.close();
}
Last edited on
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