chap 08-2

#include <math.h>
#include <stdio.h>

void fun1(float a,float b,double delt)
{
  double x[2];
    
  x[0] = -b/(2*a)-sqrt(delt)/(2*a);
    
  x[1] = -b/(2*a)+sqrt(delt)/(2*a);
    
     printf("The two roots of equation : %f,%f\n",x[0],x[1]);
}

void fun2(float a,float b,double delt)
{
  double x[2];
    
  x[0] = -b/(2*a);
    
  x[1] = x[0];
    
        printf("The two equal roots of equation : %f, %f\n",x[0],x[1]);
}


void fun3(float a,float b,double delt)
{
  printf(" the equation has no int root!");
}

void main()
{
     int a,b,c;
     double delt;
        printf("input the cof:");
     scanf("%d %d %d",&a,&b,&c);
     delt = b*b - 4*a*c;
     if(delt > 0)
     {
         fun1(a,b,delt);
     }
     else if(delt == 0)
     {
         fun2(a,b,delt);
     }
     else
     {
         fun3(a,b,delt);
     }
}

求方程ax^2+bx+c=0的根，用三个函数分别求当b^2-4ac>0,==0,<0时候的根，

并输出结果，从主函数 输入a,b,c的值