#include<stdio.h>#include<math.h>int main(){ double a,b,c,disc,p,q,x1,x2; scanf("%lf%lf%lf",&a,&b,&c); disc=b*b-4*a*c; if(a != 0) { if(disc<0) printf("\n"); else { p=-b/(2.0*a); q=sqrt(disc)/(2.0*a); x1=p+q; x2=p-q; if(disc>0) printf("%f%f\n",x1,x2); else printf("%f\n",x1); } } else if(b == 0) { if(c == 0) printf("有无限多个解\n"); else printf("无解\n"); } else { x1 = -c/b; printf("x =%f\n",x1); } return 0;}