a03.cpp

//============================================================================
// Name        : Quadratic.cpp
// Author      : 
// Version     :
// Copyright   : Your copyright notice
// Description : Hello World in C++, Ansi-style
//============================================================================

#include <bits/stdc++.h>
using namespace std;
class Quadratic{
	float a,b,c;
	public:
	Quadratic(){a=0;b=0;c=0;}
	Quadratic operator +(Quadratic &q);
	friend ostream & operator <<(ostream & out,Quadratic &q);
	friend istream & operator >>(istream & in,Quadratic &q);
	float eval(float);
	float positiveRoot();
	float negativeRoot();
	int check();
	void menu();
};
float Quadratic::positiveRoot(){
	float d=b*b-4*a*c;
	return (((-1)*b+sqrt(d))/(2*a));
}
float Quadratic::negativeRoot(){
	float d=b*b-4*a*c;
	return (((-1)*b-sqrt(d))/(2*a));
}
int Quadratic::check(){
	float d=b*b-4*a*c;
	if(d>=0)
		return 1;
	else
		return 0;
}
Quadratic Quadratic::operator +(Quadratic &q1){
	Quadratic q;
	q.a=a+q1.a;
	q.b=b+q1.b;
	q.c=c+q1.c;
	return q;
}
float Quadratic::eval(float x){
	return(a*x*x+b*x+c);
}
ostream & operator <<(ostream & out,Quadratic &q){
	if(q.b<0&&q.c<0)
		out<<"\tSum ="<<q.a<<"x^2 - "<<(-1)*q.b<<"x - "<<(-1)*q.c;
	else if(q.b<0&&q.c>=0)
		out<<"\tSum ="<<q.a<<"x^2 - "<<(-1)*q.b<<"x + "<<q.c;
	else if(q.b>=0&&q.c<0)
		out<<"\tSum ="<<q.a<<"x^2 + "<<q.b<<"x - "<<(-1)*q.c;
	else
		out<<"\tSum ="<<q.a<<"x^2 + "<<q.b<<"x + "<<q.c;
	return out;
}
istream & operator >>(istream & in,Quadratic &q){
	char x;
	in>>q.a>>x>>x>>x>>q.b>>x>>q.c;
	return in;
}
void Quadratic::menu(){
	cout<<"Press 1: Perform Addition"<<endl;
	cout<<"Press 2: to Evaluate of value of x"<<endl;
	cout<<"Press 3: to Evaluate roots"<<endl;
	cout<<"Press 0: to Exit"<<endl;
}
int main() {
	Quadratic q,q1,q2;
	char ch,op;
	float x;
	ch='1';
	label:
	cout<<"Status: ON"<<endl;
	cout<<"Enter Quadratic Equation: ";
	cin>>q1;
	q1.menu();
	y:
	cout<<endl<<"Enter Operation [0 to Exit]: ";
	cin>>op;
	switch(op){
				case '1':
					cout<<"Enter Second Quadratic Equation: ";
					cin>>q2;
					q=q1+q2;
					cout<<q<<endl;
					goto y;
					break;
				case '2':
					cout<<"Enter the Value of x: ";
					cin>>x;
					cout<<"q("<<x<<")= "<<q1.eval(x)<<endl;
					goto y;
					break;
				case '3':
					if (q1.check())
						cout<<"Roots Are: "<<q1.positiveRoot()<<" and "<<q1.negativeRoot()<<endl;
					else
						cout<<"Not Real Roots Exists"<<endl;
					goto y;
					break;
				case '0':
					cout<<"Exiting...";break;
				default : cout<<"!! Invalid choice "<<op<<" !!"<<endl;goto y;
		}
		cout<<endl<<"Do You Want to Continue?(1/0): ";
		cin>>ch;
		cout<<endl;
		if(ch!='0'){
			goto label;
		}
		else{
			cout<<"Status: OFF";
			return 0;
		}
		return 0;
}