uses crt;
var xa, xb, ya, yb, xc, yc : integer;
a, b, c, p, cv, s : real;
begin
clrscr;
write('Nhap toa do diem A : '); readln(xa, ya);
write('Nhap toa do diem B : '); readln(xb, yb);
write('Nhap toa do diem C : '); readln(xc, yc);
c := sqrt(sqr(xb - xa) + sqr(yb - ya));
a := sqrt(sqr(xc - xb) + sqr(yc - yb));
b := sqrt(sqr(xa - xc) + sqr(ya - yc));
cv := a + b + c;
p := (a + b + c) / 2;
s := sqrt(p * (p - a) * (p - b) * (p - c));
writeln('Chu vi tam giac : ', cv : 2 : 2);
writeln('Dien tich tam giac : ', s : 2 : 3);
readln
end.
