Get comments from each post. For vkontakte API execute.

eachPost_getComments.vk

var myList = Args.post_id_array_str;
var listSeparator = ",";
var listItemsType = "integer";
var result = [];
var charsLength = myList.length;
var currentPosition = 0;
var previousSeparatorPosition = -1;
var item;
while (currentPosition < charsLength) {
 if (myList.substr(currentPosition, 1) == listSeparator) {
  item = myList.substr(previousSeparatorPosition + 1, currentPosition - previousSeparatorPosition - 1);
  if (listItemsType == "integer") {
   item = parseInt(item);
  }
  result.push(item);
  previousSeparatorPosition = currentPosition;
 }
 currentPosition = currentPosition + 1;
}
var post_id;
var posts = result;
var all_comments = [];
while (posts.length != 0){post_id = posts.shift();
        var owner_id = Args.owner_id;
        var comments = API.wall.getComments(
            {"owner_id":(owner_id),
             "post_id":(post_id),
             "need_likes":"1",
             "offset":"0",
             "count":"100",
             "sort":"asc",
             "preview_length":"1",
             "extended":"0",
             "v":"5.27"});
        var comments_cnt = comments.count;
        comments = comments.items;
        var offset_comments = 100;
        while (offset_comments < comments_cnt)
            {comments = comments + API.wall.getComments(
                {"owner_id":(owner_id),
                 "post_id":(post_id),
                 "need_likes":"1",
                 "offset":(offset_comments),
                 "count":"100",
                 "sort":"asc",
                 "preview_length":"1",
                 "extended":"0",
                 "v":"5.27"}
            ).items;
        offset_comments = offset_comments + 100;};
        all_comments = all_comments+comments;
    };
return all_comments;