function find_common(arr){
console.log("NY RUNDE");
console.log(arr.length + " HEI");
  var result = [];
  var teller = 0;
  for(var a = 0; a < arr.length; a++){
      console.log("ny test "+arr[a]);
  }
  for(var i = 0; i < arr.length; i++){
    for(var j = i+1; j < arr.length; j++){
      if(arr[i] == arr[j]){
        result[teller] = arr[i];
        teller = teller + 1;
      i = i + 1;
      }
    }
  }

  var new_result = [];
  var l  = result.length;

  for(var i = 0; i < l; i++){
    for(var j = i+1; j < l; j++){
      if(result[i] == result[j]){
       new_result = find_common(result);
      }
    }
  }

  for(var a = 0; a < result.length; a++){
    console.log("tredje test "+new_result[a]);
  }
  return new_result;

}