Tips and Traps¶
Starting from Python 3.7,
dictpreserves insertion order (i.e.,dictis ordered). There is no need to useOrderedDictany more in Python 3.7+. However,setin Python is implemented as an unordered hashset and thus is neither ordered nor sorted. A trick to dedup an iterablevalues
Probability to Lose All Money

A few days ago I found someone asking an interview questions on mitbbs. The question is as follows. A gambler plays a fair game and bet 1 dollar each time. If he lose all his money, the game stops. Suppose he has 10 dollars and is only allowed to play …