80 lines
1.3 KiB
Python
80 lines
1.3 KiB
Python
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"""
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Good built in data structures is among the most important things in a good language.
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Python has several.
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"""
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# The list
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a = list()
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a = []
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a = [1, 3, 4, 5 ,6]
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# They act like expected
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for item in a:
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print(item)
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print("\n\n")
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# They can contain different types
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b = [1, "Hello", a, 3.14, lambda a : a + 1]
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for item in b:
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print(item)
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# And be mutated
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a.append(8)
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a.extend(["Hello", "World"])
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a[1] = 100
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print(a)
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print(a[:5])
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print("\n\n\n")
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# They are objects and can be inherited as such
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print(dir(a))
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class MyList(list):
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def __repr__(self):
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return "This is a useless representation"
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#pass
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b = MyList(a)
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print(b)
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# The dictionary
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# A mutable fast type agnostic hashed map
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a = dict()
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a = {}
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a = {2: "Hello world", 3: b, 8: 6.12345}
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# Note that all keys must be hashable
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# a[["Not working"]] = 3
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a[3] = ["This might work", "I think"]
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print(a)
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# They can be mutated
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a[2] = 5
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del a[3]
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print(a)
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# The keys and values can be easily red
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print(a.keys())
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print(a.values())
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# The set
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# They act like keys in dictionaries, assuming this makes using them easy
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a = set()
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a = {'apple', 'orange', 'apple', 'banana', 3, 3, 3, 3, 3}
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print(a)
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# Lists and set can be made from each other
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a = [1, 2, 3, 2, 1, 2, 3, 2, 1]
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b = set(a)
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c = list(b)
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print(a)
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print(b)
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print(c)
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