#include <stdio.h>#include<math.h>void main(){ double p,q,a,b,c,e; printf("请输入三个数:\n"); scanf("%lf,%lf,%lf",&a,&b,&c); e=b*b-4*a*c; if(e<0) printf("no!"); else { p=-b/(2.0*a);q=sqrt(e)/(2.0*a); printf("x1=%5.2f\nx2=%5.2f",p+q,p-q); } }