System Design
Observer Pattern Explained With a Real Python Example
The observer pattern lets one object announce that something happened, and lets any number of other objects react to it. The announcer kee...
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Code
Python list append time complexity: why it's amortized O(1)
Python's list.append is fast because a list is a dynamic array: one block of memory with spare slots. Most appends fill a spare slot. ...
Physics
What is momentum? Conservation of momentum and recoil
Momentum is mass times velocity (speed in a set direction): p = mv, in kilogram metres per second (kg m/s). When no outside force acts, th...
System Design
Strategy Pattern Explained With a Real Python Example
The strategy pattern hands one changeable step to a separate object. The code around it keeps the steps that never change, and calls one s...