Exercise 26 another way

[Deleted user]

I have solve exercise 26 in another way, like this:

lists.map((genre) => {
    return {
        name: genre.name,
        videos: videos.filter((video) => {
            return video.listId == genre.id;
        }).map((filtredVideo) => {
            return {
                id: filtredVideo.id,
                title: filtredVideo.title,
                time: bookmarks.filter((bookmark) => {
                    return bookmark.videoId == filtredVideo.id;
                }).map((filtredBookmark) => {
                    return filtredBookmark.time;
                })[0],
                boxart: boxarts.filter((boxart) => {
                    return boxart.videoId == filtredVideo.id;
                }).reduce((fBoxart1, fBoxart2) => {
                    return fBoxart1.width * fBoxart1.height > fBoxart2.width * fBoxart2.height ? fBoxart2 : fBoxart1;
                }).map((filtredReducedBoxart) => {
                    return filtredReducedBoxart.url;
                })[0]
            };
        })
    };
});

It's a little bit different form original code:

lists.map(function(list) {
    return {
        name: list.name,
        videos:
            videos.
            filter(function(video) {
                return video.listId === list.id;
            }).
            concatMap(function(video) {
                return Array.zip(
                    bookmarks.filter(function(bookmark) {
                        return bookmark.videoId === video.id;
                    }),
                    boxarts.filter(function(boxart) {
                        return boxart.videoId === video.id;
                    }).
                    reduce(function(acc,curr) {
                        return acc.width * acc.height < curr.width * curr.height ? acc : curr;
                    }),
                    function(bookmark, boxart) {
                        return { id: video.id, title: video.title, time: bookmark.time, boxart: boxart.url };
                    });
            })
    };
});

So please tell me... Do my solution is good? If not, why? Maybe it's not "functional thinking"?

And I act like in the first option all time, that how I'm thinking - it's seems simpler for me.