60 分

#include#include<bits/stdc++.h>
using namespace std;
int main()
{
	double a,b,c;
   scanf("%f %f %f",&a,&b,&c);
    float m = b * b - 4 * a * c ;
    if(m < 0)
    {
        printf("No answer!");
    }  
    else if (m == 0)
    {
        printf("x1=x2=%.5f",-b/2*a);
    }
    else
    {
    
       float x1 = (-b - sqrt(m)) / (2 * a);
       float x2 =  (-b + sqrt(m)) / (2 * a);
        if (x1 > x2) swap(x1,x2);
        printf("x1=%.5f;x2=%.5f",x1,x2);
    }}