uses crt;
var a,b,c :integer;
dt:real;
begin
clrscr;
writeln('Nhap a,b,c:');readln(a,b,c);
dt:=(a+b+c)/2;
If (a+b>c) and (b+c>a) and (c+a>b) then
writeln(a,', ',b,', ',c,' la ba canh cua tam giac. DT = ',sqrt(dt*(dt-a)*(dt-b)*(dt-c)):0:2)
else writeln(a,', ',b,', ',c,' khong phai ba canh cua tam giac');
readln;
end.