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Dynamic Card Game

CalcHard~25 min· Dynamic Programming
Problem

The Problem

A deck has 26 red and 26 black cards. Cards are drawn one at a time without replacement. After each draw you may stop. If you stop, your payoff is \1 \times (\text{reds drawn} - \text{blacks drawn})$ \u2014 a dollar for every red drawn so far, minus a dollar for every black drawn so far.

Questions

  1. Write the Bellman recurrence for , the expected payoff-to-go given reds and blacks remain in the deck.
  2. What is the value of the game, ?