program Sanya2263;
var a:array[1..100] of integer;
i:integer;
begin
Read(n);
For i:=1 to n do Read(a[i]);
For i:=1 to n do
if i mod 2<>0 then Write(a[i]);
end.
program Sanya2263;
var a:array[1..100] of integer;
i:integer;
begin
Read(n);
For i:=1 to n do Read(a[i]);
For i:=1 to n do
if i mod 2<>0 then Write(a[i]);
end.