#include<iostream>
#include<math.h>
#include<string>
using namespace std;
void main()
{
	string konec;
do
	{
	 float a,b,c;
	 double long d,x1,x2,x;
  	 cout<<"a=";
	 cin>>a;
	 cout<<"b=";
	 cin>>b;
	 cout<<"c=";
	 cin>>c;
	 d=((b*b)-(4*a*c));

	 if(a!=0&&b==0&&c==0)

	 cout<<"x=0"<<endl;

	 if(a==0&&b==0&&c==0)
	
	 cout<<"mnozestvo resheniy"<<endl;
	
	 if(a==0&&b!=0&&c!=0)
		{
			 x=-c/b;
			 cout<<"x="<<x<<endl;
		}
	 if(a!=0&&b==0&&c!=0)
		{			
		 if(a>0&&c>0||a<0&&c<0)
		 
			cout<<"x1="<<x1<<" "<<"x2="<<x2<<endl;
			cout<<"oshibka, vvedite znachenia zanovo"<<endl;
			continue;
		}	
     else
		{
			x1=sqrt(-c/a);
			x2=-sqrt(-c/a);
			cout<<"x1="<<x1<<" "<<"x2="<<x2<<endl;
		}
	 if(a!=0&&b!=0&&c==0)
		{
			x2=-b/a;
			cout<<"x1=0 "<<"x2="<<x2<<endl;
		}
	 if(a!=0&&b!=0&&c!=0&&d<0)         
			
			cout<<"net korney"<<endl;
			
	 if(a!=0&&b!=0&&c!=0&&d==0)
			{
				x=(-b*0.5)/(2*a);
				cout<<"x="<<x<<endl;
			}	
			
	 if(a!=0&&b!=0&&c!=0&&d>0)			
			{
				x1=((-b/2)+sqrt(d))/(2*a);
				x2=((-b/2)-sqrt(d))/(2*a);
				cout<<"x1="<<x1<<" x2="<<x2<<endl;
			}
	
	 cout<<"restart program?(y/n) ";
	 cin>>konec;
	}
while(konec=="y");
	
	
}