clear
"一元二次方程：a*x^2+b*x+c"
input "a=" to a
input "b=" to b
input "c=" to c
d=b*b-4*a*c
do case
case d0
"x1=",(b+sqrt(d))/(-2*a)
"x2=",(b-sqrt(d))/(-2*a)
endcase