program kamni;
var
  n, i, k, min, v,a,b: integer;
  m: array[1..1000] of int64;
begin
  readln(n);
  for i := 1 to n do
  begin
   read (m[i]);
  end;
  for i := 1 to n - 1 do
  begin
    min := i; for k := i + 1 to n do
      if m[min] < m[k] then min := k;
    v := m[min]; m[min] := m[i]; m[i] := v;
  end;
a:=0;
b:=0;
for i:=1 to n do
if a-b<=0 then a:=a+m[i]
else b:=b+m[i];
begin
writeln(a-b);
end;
end.

6
1 4 5 6 7 9
why 2?
9+7=16 и 1+4+5+6=16

o, senk you!)

Edited by author 02.03.2012 01:01

Thank you =))