26 lines
431 B
C++
26 lines
431 B
C++
#include<cstdio>
|
|
#include<cmath>
|
|
using namespace std;
|
|
struct Point
|
|
{
|
|
double x,y;
|
|
};
|
|
double lenth(Point A,Point B)
|
|
{
|
|
double a=abs(A.x-B.x),b=abs(A.y-B.y),c=sqrt(a*a+b*b);
|
|
return c;
|
|
}
|
|
int main()
|
|
{
|
|
Point A,B,C;
|
|
scanf("%lf%lf%lf%lf%lf%lf",&A.x,&A.y,&B.x,&B.y,&C.x,&C.y);
|
|
double a,b,c;
|
|
a=lenth(A,B);
|
|
b=lenth(B,C);
|
|
c=lenth(C,A);
|
|
double p=(a+b+c)/2.0;
|
|
double ans=sqrt(p*(p-a)*(p-b)*(p-c));
|
|
printf("%.2lf\n",ans);
|
|
return 0;
|
|
}
|