Project Review - Electricity Bill Calculating System

[thecodeinnovator]

Hi Guys,
This is a Project on A topic which I chose.
I Kindly invite your suggestions and Positive feedback on this Project !

#include <fstream.h>
#include <conio.h>
#include <stdio.h>
#include <process.h>

float dc[5]={3,3.25,3.5,4.6,6.6};
float df[3]={30,40,50};
float cf=120;


class BILL
{
	private:
		int sub_no;
		char sub_name[80];
		int unit;
		char category;
		float amount;
		void dcalc(int unit)
		{
			if((unit>0)&&(unit<=100))
				amount=df[0]+(unit*dc[0]);
			if((unit>0)&&(unit<=200))
				amount=df[0]+(unit*dc[1]);
			if((unit>200)&&(unit<=500))
			{
				amount=df[1]+(200*dc[2])+
				((unit-200)*dc[3]);
			}
			if(unit>500)
			{
				amount=df[2]+(200*dc[2])+
				(300*dc[3])+((unit-500)*dc[4]);
			}
		}
		void ccalc(int unit)
		{
			amount=cf+(unit*dc[3]);
		}
	public:
		int get_sub_no(){return sub_no;}
		char get_category(){return category;}
		void get_sub_det();
		void cdisp();
		void disp(char c);
};

void BILL::cdisp()
{
	cout<<sub_no<<"\t"<<sub_name;
	cout<<"\t\t\t"<<category;
	cout<<"\t\t"<<unit<<"\t"<<amount;
}

void BILL::disp(char c)
{
	cout<<"\nSubscriber Number         : "<<sub_no;
	cout<<"\nSubscriber Name           : ";
	puts(sub_name);
	cout<<"Category                  : "<<category;
	cout<<"\nUnits used (in Watt-Hour) : "<<unit<<"\n";
	if((c=='D')||(c=='d'))
	{
		float slab[5];
		if((unit>0)&&(unit<=100))
		{
			slab[0]=df[0];
			slab[1]=unit*dc[0];
			slab[2]=0;
			slab[3]=0;
		}
		if((unit>0)&&(unit<=200))
		{
			slab[0]=df[0];
			slab[1]=unit*dc[1];
			slab[2]=0;
			slab[3]=0;
		}
		if((unit>200)&&(unit<=500))
		{
			slab[0]=df[1];
			slab[1]=200*dc[2];
			slab[2]=(unit-200)*dc[3];
			slab[3]=0;
		}
		if(unit>500)
		{
			slab[0]=df[2];
			slab[1]=200*dc[2];
			slab[2]=300*dc[3];
			slab[3]=(unit-500)*dc[4];
		}
		cout<<"\nFixed Charges = Rs. "<<slab[0];
		int i=1;
		while(slab[i]!=0)
		{
			cout<<"\nSlab      ("<<i<<") = Rs. "<<slab[i];
			i++;
		}
	}
	else if((c=='C')||(c=='c'))
	{
		cout<<"\nFixed Charges = Rs. "<<cf;
		cout<<"\nBulk          = Rs. "<<(amount-cf);
	}
	cout<<"\n\nNet Amount : Rs. "<<amount;
	getch();
}

void BILL::get_sub_det()
{
	cout<<"\n\tData Entry :";
	cout<<"\n\t**** *****";
	cout<<"\n\nEnter Subscriber Number           : ";
	cin>>sub_no;
	cout<<"\nEnter Subscriber Name             : ";
	gets(sub_name);
	cout<<"\nEnter Category (Enter 'D' or 'C') : ";
	cin>>category;
	cout<<"\nEnter Units Consumed              : ";
	cin>>unit;
	if((category=='D')||(category=='d'))
	{
		dcalc(unit);
	}
	else if((category=='C')||(category=='c'))
		ccalc(unit);
	else
		cout<<"\nUnable to Process !!!";
}

void add_data()
{
	clrscr();
	BILL a;
	char ch='y',c;
	ofstream fout("CONSUMER.DAT",ios::binary|ios::app);
	while((ch=='y')||(ch=='Y'))
	{
		a.get_sub_det();
		fout.write((char*)&a,sizeof(a));
		cout<<"\nDo you want printed Bill ? (Y/N) :";
		cin>>c;
		if((c=='Y')||(c=='y'))
		{
			a.disp(a.get_category());
		}
		cout<<"\nProcess Another Bill ? (Y/N) :\n";
		cin>>ch;
	}
	fout.close();
}

void view_file()
{
	clrscr();
	BILL a;
	ifstream fin("CONSUMER.DAT",ios::binary);
	fin.seekg(0);
	cout<<"\nNo\tName\t\t\tCategory\tUnit\tAmount";
	cout<<"\n--\t----\t\t\t--------\t----\t------\n";
	while(fin.read((char*)&a,sizeof(a)))
	{
		a.cdisp();
		cout<<"\n";
	}
	fin.close();
}

void search()
{
	clrscr();
	BILL a;
	ifstream fin("CONSUMER.DAT",ios::binary);
	int s,c;
	cout<<"\nEnter Subscriber Number to Display :\n";
	cin>>s;
	fin.seekg(0);
	while(fin.read((char*)&a,sizeof(a)))
	{
		if(s==a.get_sub_no())
		{
			cout<<"\nDisplaying Details of Subscriber Number : "<<s;
			c=1;
			a.disp(a.get_category());
		}
	}
	if(c!=1)
		cout<<"\n\n\tNo Such Data Available to Display !!!\n\n";
	fin.close();
}

void remove()
{
	clrscr();
	BILL a;
	ifstream fin("CONSUMER.DAT",ios::binary);
	ofstream fout("temp.DAT",ios::binary);
	int n;
	char f='N';
	cout<<"\nEnter Subscriber Number to Delete :\n";
	cin>>n;
	fin.seekg(0);
	while(!fin.eof())
	{
		fin.read((char*)&a,sizeof(a));
		if(n==a.get_sub_no())
			f='Y';
		else
			fout.write((char*)&a,sizeof(a));
	}
	fin.close();fout.close();
	if(f=='Y')
		cout<<"\nDATA FOUND !\n";
	else
	{
		cout<<"\nDATA IS UNAVAILABLE !\n";
		f='U';
		goto abort;
	}
	char d;
	cout<<"Confirm Deletion ?(Y/N) :\t";
	cin>>d;
	if((d=='Y')||(d=='y'))
	{
		remove("CONSUMER.DAT");
		rename("temp.DAT","CONSUMER.DAT");
		cout<<"\nDeletion Successful !";
	}
	if((d=='N')||(d=='n'))
	{
		remove("temp.DAT");
		cout<<"\nDeletion Aborted by User !";
	}
	abort:
		if(f=='U')
			cout<<"\nABORTING DUE TO UNAVAILABLE DATA !\n";
}

void print()
{
	cout<<"\n\t\tPRESS 1 TO GO TO MAIN MENU";
	cout<<"\n\t\tPRESS 0 TO EXIT APPLICATION\n";
}

void main()
{
	clrscr();
	BILL a;
	int choice,ch;
	main:
		clrscr();
		cout<<"\n\tElectricity Bill Calculating System";
		cout<<"\n\t*********** **** *********** ******";
		cout<<"\n\n\t\t\tMAIN MENU :";
		cout<<"\n\t\t\t---- ----";
		cout<<"\n1.Add Consumer Data";
		cout<<"\n2.View All Consumers";
		cout<<"\n3.Search for a Particular Consumer";
		cout<<"\n4.Delete a Particular Consumer";
		cout<<"\n5.EXIT\n";
		cin>>ch;
		switch(ch)
		{
			case 1:
				add_data();
				print();
				cin>>choice;
				if(choice==1)
					goto main;
				else
					goto exit;
			case 2:
				view_file();
				print();
				cin>>choice;
				if(choice==1)
					goto main;
				else
					goto exit;
			case 3:
				search();
				print();
				cin>>choice;
				if(choice==1)
					goto main;
				else
					goto exit;
			case 4:
				remove();
				print();
				cin>>choice;
				if(choice==1)
					goto main;
				else
					goto exit;
			case 5:
				goto exit;
		}
	exit:
		cout<<"\n\nTHANKYOU FOR USING THIS APPLICATION !!!\n";
		for(int k=0;k<200;k++)
		{
			//Time Delay for-loop
		}
	getch();
}


//Project:Electricity_Bill_Calculator_Lines:310_Length:5937 

P.S : I know that this requires an older version of Neutron C++ . Thats because we are instructed to use this version only.

[jlb]

This is a Project on A topic which I chose.

And just what is this project supposed to be doing?


goto Really? Learn one of the other more accepted looping constructs.

[AbstractionAnon]

The only comment in the program is line 304. Do you really expect someone to understand your program without meaningful comments?

As jlb said gotos are evil.

Lines 6-8: What are these (the names are meaningless) and why are they global?

Line 162,179,206,210: These statements only work because BILL is Plain Old Data (POD). If BILL were to contain any complex data types such as std::string, these statement would not work.

Line 246: main must be type int.

Line 249: Why is BILL declared here? It's not used in main.

Lines 267-272: Why are these statements repeated in each branch of the case since they apply to all branches. Move these statements after the switch statement.

Lines 302-305: A good optimizing compiler is going to remove these lines since they serve no purpose.


Line 251: A label with the same name as your function. Confusing and a poor practice.

Line 300: A label with the same name as a standard function exit(). Again confusing and a poor practice.

[thecodeinnovator]

AbstractionAnon wrote:

Confusing and a poor practice.

but i am still a beginner only and i am not a programming genius like you all that is why i post my doubts so as to clear them as early as possible.
if you say it is a poor practise thak you for your generous critisism , i hope i can learn from you ,how to harass any one who is new to c++.

thank you !

[thecodeinnovator]

jlb wrote:

And just what is this project supposed to be doing?

This is a Program to Calculate Energy consumption for a Household in kWh.

[AbstractionAnon]

i hope i can learn from you ,how to harass any one who is new to c++.

The intent was never to harass you. Sorry if you felt harassed. My only intent was to guide you to better programming practices.