var
  a,b:array [1..101] of longint;
  k:longint;
procedure init;
  var
    i:longint;
  begin
    fillchar(a,sizeof(a),0);
    readln(k);
    for i:=1 to k do
       read(a[i]);
  end;
procedure work;
  var
    k1,t,max,i,j,min,jl:longint;
  begin
    k1:=0;
    max:=0;
    min:=a[1];
    k1:=trunc(k/2)+1;
    for i:=1 to k-1 do
      for j:=1 to k-1 do
        begin
          if min>a[j+1] then begin min:=a[j+1]; jl:=j+1; end;
          if j=k-1 then begin b[i]:=min; a[jl]:=10002; min:=a[i]; end;
        end;
        for i:=1 to k1 do
        max:=max+(trunc(b[i]/2)+1);
     writeln(max);
  end;
begin
  init;
  work;
end.

try test:

6
1 5 9 3 7 11

answer: 10

Why you not sort array???

Sory? but my test is incorrect...
try this test

5
3 5 7 9 11

answer: 9