这个代码有逻辑错误，修改下

题目是：
输入三个点坐标
若该三点能构成三角形则输出周长和面积，否则输出Impossible;
现在只能输出Impossible。

#include 
int main()
{
   double a,b,c,d,e,f,g,h,i,k;
   scanf("%lf,%lf\n",&a,&b);
   scanf("%lf,%lf\n",&c,&d);
   scanf("%lf,%lf\n",&e,&f);
   g=sqrt((a-c)*(a-c)-(b-d)*(b-d));
   h=sqrt((c-e)*(c-e)-(d-f)*(d-f));
   i=sqrt((a-e)*(a-e)-(b-f)*(b-f));
   if(g+h&&g+i&&i+h"primer=%.2f,area=%.2f",g+h+i,sqrt(k*(k-g)*(k-h)*(k-i)));
   }else{
       printf("Impossible");
   }
   return 0;
}

计算两点间距离有误，应该是相加，不是相减

g=sqrt((a-c)*(a-c)+(b-d)*(b-d));
   h=sqrt((c-e)*(c-e)+(d-f)*(d-f));
   i=sqrt((a-e)*(a-e)+(b-f)*(b-f));

#include<stdio.h>
#include<math.h>
int main(void)
{
    double x1,y1,x2,y2,x3,y3;
    double l1,l2,l3;
    double L,A;
    scanf("%lf %lf %lf %lf %lf %lf",&x1,&y1,&x2,&y2,&x3,&y3);
    
    l1=sqrt(pow((x1-x2),2)+pow((y1-y2),2));
    l2=sqrt(pow((x2-x3),2)+pow((y2-y3),2));
    l3=sqrt(pow((x1-x3),2)+pow((y1-y3),2));
    
    if(l1+l2>l3&&l1+l3>l2&&l2+l3>l1){
     L=l1+l2+l3;
    float p=L/2.0;
    A=sqrt(p*(p-l1)*(p-l2)*(p-l3));
     printf("L = %.2f, A = %.2f",L,A);
    }
    else
    printf("Impossible");
    
    return 0;
}