program nho_nhat;
uses crt;
var a,b,c,d:integer;
{---ham-tim-lon-nhat---}
function max(a,b,c,d:integer):integer;
begin
max:=a;
if b>max then max:=b;
if c>max then max:=c;
if d>max then max:=d;
end;
{---Chuong-trinh-chinh---}
BEGIN
clrscr;
write('Nhap so thu nhat: '); readln(a);
write('Nhap so thu hai: '); readln(b);
write('Nhap so thu ba: '); readln(c);
write('Nhap so thu tu: '); readln(d);
write('So lon nhat la: ',max(a,b,c,d));
readln;
end.
