a)
var a,b:longint;
begin
write('Nhap chieu dai: '); readln(a);
write('Nhap chieu ong '); readln(b);
writeln('Chu vi la: ',2*(a+b));
write('Dien tich la: ',a*b);
readln
end.
b)
var x:longint;
begin
write('Nhap x: '); readln(x);
write('BInh phuong cua x la: ',x*x);
readln
end.