Var i,n:integer;
p:longint;
Begin
Write('Nhap n = ');readln(n);
p:=0;
For i:=2 to n do p:=p*i;
Write('Tich la ',p);
Readln;
End.
Var i,n:integer;
p:longint;
Begin
Write('Nhap n = ');readln(n);
p:=1;
For i:=2 to n do p:=p*i;
Write('Tich la ',p);
Readln;
End.