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

int main(){
	float ax,ay,bx,by,cx,cy,a,b,c,O,S,P;

	printf("Unesite koordinate svih 6 tacaka: ");
	scanf("%f %f %f %f %f %f", &ax,&ay,&bx,&by,&cx,&cy);
	
	a = sqrt((bx-cx)*(bx-cx)+(by-cy)*(by-cy));
	b = sqrt((ax-cx)*(ax-cx)+(ay-cy)*(ay-cy));
	c = sqrt((bx-ax)*(bx-ax)+(by-ay)*(by-ay));

	O = a+b+c;
	S = O/2;
	P = sqrt(S*(S-a)*(S-b)*(S-c));
	
	printf("O = %f\t P = %f\n", O, P);

	return 0;
}