Chương trình trong Free Pascal:
program HCN;
uses crt;
var a, b, P, S: integer
begin
clrscr;
write('Nhap chieu dai HCN: '); readln(a);
write('Nhap chieu rong HCN: '); readln(b);
P:=(a+b)*2; writeln('Chu vi cua HCN la: ', P);
S:=a*b; writeln('Dien tich cua HCN la: ', S);
readln;
end.