☕ Amazon Fails
Amazon shuts down a business that they've been investing in for 4 years. A mental health start up raises a monster round of financing. A Google Interview Question.
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Interview Problem
What is Leader Election in the context of System Design and Distributed Computing?
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Industry News
Amazon cancels Crucible, it’s free to play multiplayer shooter
If you’re like most people, you were probably unaware that Amazon had a free-to-play multiplayer shooter called Crucible. It was Amazon’s response to Fortnite, the massive free-to-play, team-based shooter by Epic Games. The company planned to integrate it further with Twitch, a video game streaming service that Amazon acquired in 2014. Crucible was launched in May after years of development (it was first announced in 2016), but Amazon put it back into closed beta in July (due to abysmal traction).
Now, the company has cancelled Crucible, just five months after release. They’ll be giving users a full refund for any purchases made (through microtransactions) and servers will stay up until November 9th for custom games. The financial loss for this kind of termination would be in the tens of millions of dollars.
If you’re familiar with Amazon’s culture, however, this kind of failure is no big surprise. Amazon thrives on bold mistakes so that the company can continue to innovate fearlessly. After Amazon’s massive failure with the Fire Phone in 2015 (resulting in the loss of hundreds of millions of dollars), Bezos sent the following message to the leader of the Fire Phone project.
“You can’t, for one minute, feel bad about the Fire Phone. Promise me you won’t lose a minute of sleep”
This kind of culture is how you build a trillion dollar company.
This is also not the end for Amazon’s gaming interests, it’s just the beginning. Amazon is investing heavily in a cloud gaming service called Luna that was launched last month. Luna offers all-you-can-play access to different selections of games as part of separate “channels”, similar to a cable service. An example is the Ubisoft channel, which gives users a bundle of Ubisoft games. You purchase access to the channel and get all the games contained.
Digital mental health subscription service Cerebral raises $35 million dollars
The mental health market is incredibly hot in digital health. In the first half of 2020, digital behavioral health companies raised $588 million dollars in funding, with several companies receiving over $100 million dollars. Headspace is one of those companies with a Series C round that was over $100 million dollars.
Cerebral is another company in the space and has raised $35 million dollars in their Series A. The company offers a membership service where clients can get telehealth visits with a mental health provider and monthly chats with a care counselor. The provider can come up with a treatment plan, which may include medication. They can then use Cerebral to ship the medication to clients through mail and see the patient’s symptoms and side-effects through the app.
Cerebral will be using the $35 million dollars to expand into all 50 states and also expand partnerships with insurers. The money was raised in a round led by Oak HealthCare with participation from Liquid 2 Ventures, Gaingels and Air Angels.
Previous Solution
As a refresher, here’s the previous question
Given two integers n and k, return all possible combinations of k numbers out of 1 to n inclusive.
You can return the answer in any order!
Input - n = 4, k = 3
Output - [[1,2,3],[1,2,4],[1,3,4],[2,3,4]]
Solution
This question is quite similar to the permutations question we sent out a couple of days ago.
The way you solve it is through backtracking or DFS.
In backtracking, you
Make a Choice
Explore that Choice until you’ve reached an end
Undo the Choice
So, in terms of building finding all the combinations of n characters that are of length k, we first start with the empty string, then we backtrack
Make a choice - pick one of the n characters to add to our string
Explore the choice - recursively call our function on the remaining n - 1 characters and k - 1 spots, until we run out spots (k will always be less than n). When we run out of spots (k), then we add our string to a set where we keep track of all combinations.
Undo the choice - delete that one of n characters that we picked.
Here’s the Python 3 code (with test cases!) for how we can do this.