var levels = new Array();

  levels.push(new Array($A(["mous", "opti", "pico", "funb", "topa", "dart", "class", "f317j", "f317s", "pav"]), 'Débutant', 'beginner'));

  levels.push(new Array($A(["opti", "pico", "funb", "topa", "dart", "pav"]), 'Initiation', 'intermediate'));

  levels.push(new Array($A(["opti", "pico", "funb", "topa", "dart", "pav"]), 'Perfectionnement', 'perf'));

  levels.push(new Array($A(["catp"]), 'Après perfectionnement', 'after_perf'));

  levels.push(new Array($A(["class", "f317j", "f317s"]), 'Confirmé', 'pro'));


function activitySelected() {
  activity_value = $('search_activity').getValue();
  options = $('search_level').options;
  options.length = 1;
  levels.each(function(level) {
    if (level[0].indexOf(activity_value) != -1) {
      options[options.length] = new Option(level[1], level[2]);
    }
  });
}

document.observe('dom:loaded', function() {
  $('search_activity').observe('change', activitySelected);
});