其实只要换个思维就会很简单啊
一遍AC，
附标程：
var a:array[0..32767] of longint;
i,n,s,x,k:longint;
begin
readln(n,k);
for i:=1 to n do
begin read(x);a[x]:=a[x]+1;end;
for i:=32767 downto 0 do
if a[i]<>0 then begin
s:=s+a[i];
if s>=k then begin writeln(i);halt;end;
end;
end.