求一组数的中位数

巨羡慕C党有sort用

Program P2388;
var
   n,i,j:longint;
   a:array[1..10010] of longint;
Procedure qsort(l,r:longint);
var
   i,j,m,p:longint;
begin
   i:=l;
   j:=r;
   m:=a[(l+r) shr 1];
   repeat
      while a[i]<m do inc(i);
      while a[j]>m do dec(j);
      if i<=j then
      begin
         p:=a[i];a[i]:=a[j];a[j]:=p;
         inc(i);dec(j);
      end;
   until i>j;
   if l<j then qsort(l,j);
   if i<r then qsort(i,r);


end;
begin
   read(n);
   for i:=1 to n do read(a[i]);
   qsort(1,n);
   writeln(a[(1+n) shr 1]);
end.