$ include "seed7_05.s7i";

const proc: main is func
  local
    const array integer: s is [] (1, 2, 2, 3, 4, 4, 5);
    var integer: i is 0;
    var integer: curr is 0;
    var integer: prev is 0;
  begin
    for i range 1 to length(s) do
      curr := s[i];
      if i > 1 and curr = prev then
        writeln(i);
      end if;
      prev := curr;
    end for;
  end func;