Uses crt;

Var x, y, z, t, max: real;

Begin

   Clrscr;

   Write('Nhap so x = '); readln(x);

   Write('Nhap so y = '); readln(y);

   Write('Nhap so z = '); readln(z);

   Write('Nhap so t = '); readln(t);

   max:=x;

   If y>max then max:=y;

   If z>max then max:=z;

   If t>max then max:=t;

   Writeln('So lon nhat la: ',max:4:2);

Readln

End.

uses crt;

  var a, b, c, d, max: real;

begin

  clrscr;

  write('Nhap a = '); readln(a);

  write('Nhap b = '); readln(b);

  write('Nhap c = '); readln(c);

  write('Nhap d = '); readln(d);

  max:=a;

  if max<b then max:=b;

  if max<c then max:=c;

  if max<d then max:=d;

  write(max, ' la so lon nhat.');

  readln

end.