Bài 1:
program tinh_Tich;
uses crt;
var n,i:integer;
tich:longint;
begin
clrscr;
write('Nhap N: '); readln(n);
tich:=1;
for i:=1 to n do tich:=tich*i;
write('Tich cac so tu 1 den ',n,' la: ',tich);
readln;
end.
Bài 2:
program nguyen_to;
uses crt;
var n,i,d:integer;
begin
clrscr;
write('Nhap N: '); readln(n);
d:=0;
for i:=1 to n do
if n mod i=0 then d:=d+1;
if d=2 then write('La so nguyen to')
else write('Khong phai so nguyen to');
readln;
end.