1.
var x,y,kq.i:longint;
begin
kq:=1;
write('Nhap x,y: '); readln(x,y);
for i:=1 to y do
kq:=kq*i;
write('Ket qua la: ',kq);
readln;
end.
2.
var i,n,kq:longint;
begin
write('Nhap n: '); readln(n);
kq:=1;
for i:=1 to n do
kq:=kq*i;
write('Giai thua cua n la: ',kq);
readln;
end.