Jane Street–styleInternInternQuestion #533
You roll a six-sided die and receive the amount you roll in cash. How much should you pay to play this game? What if you do not like your first roll and are allowed to roll exactly once more (but you must take what you get the last time)? What if you can roll up to three times, always keeping the last roll? What if you can roll infinitely many times?
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More Jane Street–Style Intern Questions
Design a real-time system to process millions of trades per second. How would you ensure low latency, fault tolerance, and exactly-once processing?If I roll two dice, what is the expected value of the product of the two faces?Suppose we play a game with a die where we roll and sum our rolls. We can stop at any time, and the sum is our score. However, if our sum is ever a multiple of 10, our score becomes zero and our game is over. What strategy will yield the greatest expected score? What about if the target multiple is a value other than 10?Implement the game Tetris in 30 minutes.What is the optimal strategy for winning in rock-paper-scissors if your opponent can only choose between rock and paper?
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