Can anyone please help me to understand the solution of this problem?
ZOJ: 3329: One Person Game
Solution link
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Can anyone please help me to understand the solution of this problem?
ZOJ: 3329: One Person Game
Solution link
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Define f(x) as the expected number of dice rolls if the current number is x. We can express f(x) in the form f(x) = k + a·f(0). Then when we get to f(0) we can use simple algebra to solve for the answer: