main.cpp

#include<iostream>
#include<fstream>
#include<windows.h>
#include<sstream>
using namespace std;

class Airline {
private:
	string Flight, Des, Dep;
	int Seats;

public:
	Airline(string flight, string des, string dep, int seats) {
		Flight = flight;
		Des = des;
		Dep = dep;
		Seats = seats;
	}

	string getFlight() {
		return Flight;
	}


	string getDes() {
		return Des;
	}

	string getDep() {
		return Dep;
	}

	int getSeat() {
		return Seats;
	}

	void update(string flight) {
		ifstream in("D:/Flight.txt");
		ofstream out("D:/Flight Temp.txt");

		string line;
		while (getline(in, line)) {
			int pos = line.find(flight);
			if (pos != string::npos) {

				int current = Seats - 1;
				Seats = current;
				stringstream ss;
				ss << current;
				string strCurrent = ss.str();

				int seatPos = line.find_last_of(':');
				line.replace(seatPos + 2, string::npos, strCurrent);

			}
			out << line << endl;
		}
		out.close();
		in.close();
		remove("D:/Flight.txt");
		rename("D:/Flight Temp.txt", "D:/Flight.txt");
		cout << "Seat Reserved Successfuly!" << endl;
	}

};

void display() {
	ifstream in("D:/Flight.txt");
	if (!in) {
		cout << "Error: File Can't Open!" << endl;
	}
	else {
		string line;
		while (getline(in, line)) {
			cout << line << endl;
		}
	}
}

int main() {
	Airline flight1("F101", "UAE", "England", 50);
	Airline flight2("F202", "UAE", "USA", 40);
	Airline flight3("F303", "UAE", "Canada", 2);

	ofstream out("D:/Flight.txt");
	if (!out) {
		cout << "Error: File can't open!" << endl;
	}
	else {
		out << "\t " << flight1.getFlight() << " : " << flight1.getDes() << " : " << flight1.getDep() << " : " <<
			" : " << flight1.getSeat() << endl << endl;

		out << "\t " << flight2.getFlight() << " : " << flight2.getDes() << " : " << flight2.getDep() <<
			" : " << flight2.getSeat() << endl << endl;

		out << "\t " << flight3.getFlight() << " : " << flight3.getDes() << " : " << flight3.getDep() <<
			" : " << flight3.getSeat() << endl << endl;

		cout << "Data Saved Successfuly!" << endl;
		out.close();
	}

	bool exit = false;
	while (!exit) {
		system("cls");
		cout << "\t Welcome To Airline Management System" << endl;
		cout << "\t ************************************" << endl;
		cout << "\t 1.Reserve A Seat." << endl;
		cout << "\t 2.Exit." << endl;
		cout << "\t Enter Your Choice: ";
		int val;
		cin >> val;

		if (val == 1) {
			system("cls");
			display();
			string flight;
			cout << "Enter Flight No: ";
			cin >> flight;

			if (flight == flight1.getFlight() && flight1.getSeat() > 0) {
				flight1.update(flight);
			}
			else if (flight1.getSeat() <= 0) {
				cout << "Sorry, Seats Not Available!" << endl;
			}

			if (flight == flight2.getFlight() && flight2.getSeat() > 0) {
				flight2.update(flight);
			}
			else if (flight2.getSeat() <= 0) {
				cout << "Sorry, Seat Not Available!" << endl;
			}

			if (flight == flight3.getFlight() && flight3.getSeat() > 0) {
				flight3.update(flight);
			}
			else if (flight3.getSeat() <= 0) {
				cout << "Sorry, Seat Not Available!" << endl;
			}
			Sleep(5000);
		}

		else if (val == 2) {
			system("cls");
			exit = true;
			cout << "Good Luck!" << endl;
			Sleep(3000);
		}
	}
}