real a,b,c
read *,a,b,c	
diskr= b*b-4.*a*c

if(deskr.lt.0)then
x1=(-b+sqrt(-deskr))/(2.*a)
x2=(-b-sqrt(-deskr))/(2.*a)
print *,"root on complex = ",x1,"+i",x2,x1,"-i",x2
stop
endif
if(deskr.eq.0)then
x1=-b/(2.*a)
print*,"root on=",x1
stop
endif

if(deskr.gt.0)then
x1=(-b+sqrt(deskr))/(2.*a)
x2=(-b-sqrt(deskr))/(2.*a)
print*,"root on=",x1,"  ",x2
stop
endif

end