rongpenl

# https://youtu.be/AtjXJVEgwqg?si=361RqZqCvRvJure0

from manim import *
class Extension4AnyRationalNumberQ2(Scene):
    # what's the shortest n
    # https://en.wikipedia.org/wiki/Greedy_algorithm_for_Egyptian_fractions#:~:text=An%20Egyptian%20fraction%20is%20a,%3D%2012%20%2B%2013.
    # https://r-knott.surrey.ac.uk/Fractions/egyptian.html#section5.2
    def construct(self):
        self.camera.background_color = "#F1F3F8"
        question = Tex(

rongpenl

# Ron and Math: https://www.youtube.com/post/Ugkx-VJIlzGcL15mA4wX1kpkuKZq3634vYrh

def frog_jump():
    steps = {(0,0): 1}
    for x in range(5):
        for y in range(5):
            if (x,y) not in steps:
                steps[(x,y)] = steps.get((x-1,y),0) + steps.get((x-2,y),0) + steps.get((x,y-1),0) + steps.get((x,y-2),0)
    return steps[(4,4)] # 556

rongpenl

# ron and math community post: https://www.youtube.com/post/Ugkx321bNyuBEYuPthOIEKpbaqz04Ujat1f_
def a(n):
  if n < 3:
    return 1
  if n not in memo_a:
    memo_a[n] = a(n - 2) + a(n - 3)
  return memo_a[n]

def b(n):
  if n not in memo_b:

rongpenl

def head_1(statement: bool):
    if statement:
        return True
    else:
        return False
    
def head_2(statement: bool):
    if statement:
        return False
    else:

rongpenl

def A(n,i):
    # calculate using a simulation approach.
    i = i-1 # convert to 0-based index.
    urinals = np.zeros(n)
    urinals[i] = 1 # the ith is occupied.
    while True:
        # find the furtherest urinal that is away from any occupied urinal.
        candidates = {} # key: the index of the urinal, value: the distance to the nearest occupied urinal.
        for j in range(n):
            if urinals[j] == 1:

rongpenl

from threading import Lock
import sqlite3
import requests

# thread lock example
lock = Lock()

with lock:
    # Critical section of code
    print("Critical section running")

rongpenl

from coach import Coach

class ActivityManagedCoach(Coach):
    def __enter__(self):
        self.warm_up_players()
        return self

    def __exit__(self, exc_type, exc_val, exc_tb):
        self.host_retro_meeting()
        print(f"Exception type: {exc_type}")

rongpenl

from contextlib import contextmanager


@contextmanager
def open_file(path, mode):
    try:
        file = open(path, mode)
        yield file
    finally:
        file.close()

rongpenl

from contextlib import contextmanager
from coach import Coach

@contextmanager
def activity_management(coach: Coach):
    try:
        coach.warm_up_players()
        yield coach
    finally:
        coach.host_retro_meeting()

rongpenl

from typing import Callable

class Coach:
    def warm_up_players(self):
        print("The coach is warming up the players.")

    def host_retro_meeting(self):
        print("The coach is having a retro meeting after the game.")

    def coach_game(self):