moar things
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@ -69,3 +69,127 @@ and_var = bool1 and bool2 # False
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or_var = bool1 or bool2 # True
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or_var = bool1 or bool2 # True
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not_var = not bool1 # False
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not_var = not bool1 # False
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xor_var = bool1 ^ bool2 # True
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xor_var = bool1 ^ bool2 # True
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"""
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Strings support basic operations, like repetition, and joining them together
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You can think of strings as simply being a list of characters. Because of this, most list operations
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also apply to strings. We will cover those in a minute
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But they also have more things you can do to them by using 'methods' on them
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Some of the demonstrated methods include:
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.split(at) => Splits the string into a list of substrings at the provided split point
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.capitalize() => Capitalizes the string
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.startswith(str), .endswith(str) => Check if the string starts with another string and ends with another string
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Your editor should tell you all the methods available to you if you type out the string variable name and a dot
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"""
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string1 = "Skynet is "
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string2 = "Catlover"
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string3 = "Coming"
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sum_var = string1 + string3 # "Skynet is Coming"
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product_var = string2 * 3 # CatloverCatloverCatlover
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words = sum_var.split(" ") # Splits into words ["Skynet", "is", "Coming"]
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capital = sum_var.capitalize() # Capitalizes "SKYNET IS COMING"
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startswith = sum_var.startswith("Skynet") # True
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endswith = sum_var.endswith("Peanuts") # False
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"""
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Lists are one of the most useful data types in python, specifically when it comes to algorithms of any kind
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You are able to:
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get the length of the list
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get elements at specific positions of the list
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get subsets of the list using slicing
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A quirk of lists in most programming languages is that they start at the 0th element
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this is because the index is historically an offset from the first element in the list
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But algorithmically, a zero-indexing system is surprisingly nicer to work with
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In python, slicing is not inclusive of the final element
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If you omit either end of the slicing operation, it implicitly takes the rest of the array
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You can also do things like appending and repeating arrays
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"""
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list1 = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
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length = len(list1) # Gets the length of the list => 10
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first = list1[0] # Gets the first element of the list => 1
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second = list1[1] # Gets the second element of the list => 2
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last = list1[-1] # Gets the last element of the list => 10
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first_five = list1[0:5]
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# is also
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first_five = list1[:5]
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last_five = list1[5:10]
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# is also
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last_five = list1[5:]
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list2 = last_five + first_five # We have swapped the first and last 5 elements around
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rep = first_five * 3 # [1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5]
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list2.append(27) # We can add a new element to the list
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list2.sort() # The elements of list2 get sorted (in-place)
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list2.reverse() # We reverse the sorted list
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one = list2.pop() # Remove the last element from the list (list2[-1]) which is 1
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print(list2)
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"""
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Dictionaries are the final builtin type we are covering
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They allow us to map elements to other elements, and subsequently look them up
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They do this quite efficiently
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"""
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months_abbreviations = {
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"Jan" : "January",
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"Feb" : "February",
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"Mar" : "March",
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"Apr" : "April",
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"May" : "May",
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"Jun" : "June",
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"Jul" : "July",
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"Aug" : "August",
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"Sep" : "September",
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"Oct" : "October",
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"Nov" : "November",
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"Dec" : "December"
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}
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months_abbreviations["Jan"] # "January"
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del months_abbreviations["Sep"] # We just delete september, who liked it anyway?
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months_abbreviations["Ala"] = "Alabama" # Who said states cant be months?
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"""
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Dictionaries are a very robust type, and can also be used for things like tracking users and their scores
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"""
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users = {
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"mario" : 11,
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"luigi" : 13,
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"peach" : 17,
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"starfox" : 174
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}
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