Easy program for calculate quadratic equation

Category: Homework in Pascal

Author: scoooby
web: www.chlievik.net

Program: Krovnica.pas
File exe: Krovnica.exe

{ KROVNICA.PAS                                                      }
{ Jednoduchy program na vypocet kvadratickej rovnice.               }
{                                                                   }
{ Author: scooby (www.chlievik.net)                                 }
{ Datum:28.01.2005                            http://www.trsek.com  }
 
program kvrovnica;
uses crt;
var A,B,C,D,X,X1,X2,X3:real;
 
begin
  clrscr;
  writeln ('Napis cinitele kvadratickej rovnice');
  readln (A,B,C);
  D:=(B*B)-(4*A*C);
 
  if A<>0 then
    if D>0 then begin
       X1:=(-B+sqrt(D))/(2*A);
       X2:=(-B-sqrt(D))/(2*A);
       writeln ('P={',X1:5:2,',',X2:5:2,'}');
    end
    else
    if D=0 then begin
       X:=-B/(2*A);
       writeln ('P={',X:5:2,'}');
    end
    else writeln ('P={}')
      else if B<>0 then begin
              X3:=-C/B;
              writeln ('P{',X3,'}');
           end
           else if C=0 then  writeln ('P=R')
                        else writeln ('P={}');
 
  readln;
end.