program zad;
var a,n,i:longint;
b:array[1..1000] of real;
begin
n:=0;
while not eof do begin
read(a);
n:=n+1;
b[n]:=sqrt(a);
end;
for i:=n downto 1 do
writeln(b[i]:0:4);
end.

nvrm, fixed it.

As I  think, u should  use dynamic array.