xuhang57

uname -r
sudo su
# useradd builder
# groupadd builder
cd /home/centos
# Get Source Code
wget http://vault.centos.org/7.2.1511/updates/Source/SPackages/kernel-3.10.0-327.28.3.el7.src.rpm
rpm -ivh kernel-3.10.0-327.28.3.el7.src.rpm

# Build Preparation

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# https://stackoverflow.com/questions/12179271/meaning-of-classmethod-and-staticmethod-for-beginner/12179325#12179325

# @classmethod means: when this method is called, we pass the class as the first argument instead of 
# the instance of that class (as we normally do with methods). 
# This means you can use the class and its properties inside that method rather than a particular instance.

# @staticmethod means: when this method is called, we don't pass an instance of the class to it
# (as we normally do with methods). 
# This means you can put a function inside a class but you can't access the instance of that class 
# (this is useful when your method does not use the instance)

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# https://stackoverflow.com/a/33469090/8379419
  
# Dependency Injection

# Other people can use your code and inject parents into the method resolution:

class SomeBaseClass(object):
    def __init__(self):
        print('SomeBaseClass.__init__(self) called')

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Keybase proof

I hereby claim:

• I am xuhang57 on github.
• I am xuhang57 (https://keybase.io/xuhang57) on keybase.
• I have a public key ASDZtjCtXp-eu8ix7SewdhQHIQRiVfstD3xYhWV015a8xAo

To claim this, I am signing this object:

xuhang57

def merge(left, right):
    res = []
    i, j = 0, 0
    
    while i < len(left) and j < len(right):
        if left[i] <= right[j]:
            res.append(left[i])
            i+=1
        else:
            res.append(right[j])

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def insertion_sort(arr):
    for i in range(1, len(arr)):
        cur_val = arr[i]
        
        # indexes of the previous values
        j = i-1
        
        while j>=0 and cur_val < arr[j]:
            arr[j+1] = arr[j]
            j -= 1

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def selection_sort(arr):
    for i in range(len(arr)):
        min_idx = i
        for j in range(i+1, len(arr)):
            if arr[min_idx] > arr[j]:
                min_idx = j
                
        arr[i], arr[min_idx] = arr[min_idx], arr[i]
    
    return arr

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def quick_sort(arr):
    smaller, equal, greater = [], [], []
    
    if len(arr) > 1:
        pivot = arr[0]
        for x in arr:
            if x < pivot:
                smaller.append(x)
            elif x == pivot:
                equal.append(x)

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# String
string = ""

# Tuple
t = tuple() # (), (1,)

# List (Array)
l = []

# Stack, LIFO

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# --------
# Hardware
# --------

# Opcode - operational code
# Assebly mnemonic - abbreviation for an operation

# Instruction Code Format (IA-32)
# - Optional instruction prefix
# - Operational code