Amazing-Python-Scripts

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''' 
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LISTS
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    A list is a data structure in Python that is a mutable, or changeable, ordered sequence of elements
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Advantage of List over Linked List:
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    Elements can be accessed through their index value
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BigO of Array:
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    Indexing -----> O(1)
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    Insert/Delete element at Start -----> O(n)
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    Insert/Delete element at End -----> O(1)
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    Insert element at Middle -----> O(n)
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'''
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# Empty List
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list = []
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print(f"This is an Empty List: {list}\n")
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# List with Elements
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list = [1, 2, 3.1, "A"]
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print(f"Elements of the list are: {list}\n")
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''' Adding elements '''
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print("**********Adding Elements**********", end="\n\n")
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# add as a single element
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list.append(["B", 4])
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print("Appended List ", list, end="\n\n")
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# add as different elements
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list.extend([5, 'E'])
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print("Entended List ", list, end="\n\n")
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# add element at 1st Index
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list.insert(0, 0)
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list.insert(5, "F")
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print("Inserted Element ", list, end="\n\n")
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''' Deleting Elements '''
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print("**********Deleting Elements**********", end="\n\n")
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# delete element at index 5
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del list[5]
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print("Deleted element ", list, end="\n\n")
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# remove element with value '<val>'
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list.remove('E')
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print("Removed element ", list, end="\n\n")
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# pop element from list at i^th index
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a = list.pop(1)
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print('Popped Element: ', a, ' List remaining: ', list, end="\n\n")
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# empty the list
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list.clear()
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print("Empty List ", list, end="\n\n")
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''' Accessing Elements '''
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print("**********Accessing Elements**********", end="\n\n")
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list = [1, 2, 3.5, "A", True]
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print("This is new list ", list, end="\n\n")
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# access elements one by one
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print("Accessing all Elements one by one\n")
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for element in list:
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    print(element, end="\n")
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# access all elements
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print("\nAccessing all elements\n")
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print(list, end="\n\n")
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# access index i element
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print("Element at index=2 is", list[2], end="\n\n")
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# access elements from 0 to 1 and exclude 2
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print("Elements from index(0 to 1) are ", list[0:2], end="\n\n")
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# access elements in reverse
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print("Elements in reverse order ", list[::-1], end="\n\n")
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''' 
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Other Functions 
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    len() : returns length of the list.
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    index() : finds index value of value passed where it has been encountered the first time.
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    count()  : finds count of the value passed to it.
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    sorted() and sort() : to sort the values of the list. 
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    sorted() has a return type whereas the sort() modifies the original list.
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'''
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print("**********Other Functions**********", end="\n\n")
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list = [1, 2, 3, 10, 20, 50]
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# find length of list
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print("No of elements in the list ", len(list), end="\n\n")
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# find index of element that occurs first
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print("Index of element 20 is ", list.index(20), end="\n\n")
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# find count of the element
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print(f"Elements has been repeated {list.count(10)} time", end="\n\n")
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# print sorted list but not change original
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print("Sorted list is [AESC] ", sorted(list), end="\n\n")
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# sort original list
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list.sort(reverse=True)
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print("Sorted list is [DESC]", list, end="\n\n")
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