Amazing-Python-Scripts

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"""
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Selection Sort
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Time Complexity: O(n^2)
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"""
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def FindMin(arr):
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    """finds minimum element from the list"""
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    min = 100000  # let list contain +ve numbers only: so minimum number is -1
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    for i in range(len(arr)):
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        if arr[i] < min:
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            min = arr[i]
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    return min
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def SelectionSort(arr):
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    size = len(arr)
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    for i in range(size-1):  # decreased 1 iteration: no need to iterate to the last element
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        minIndex = i  # pointer initialised to ith index for selection sort
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        for j in range(minIndex+1, size):
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            if arr[j] < arr[minIndex]:  # if current index < minimum index of the array
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                minIndex = j  # minimum index updated
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        # swapping element
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        if i != minIndex:
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            arr[i], arr[minIndex] = arr[minIndex], arr[i]
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if __name__ == '__main__':
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    elements = [100, 19, 28, 14, 6, 1, 99]
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    print(FindMin(elements))  # prints minimum element from the list
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    SelectionSort(elements)
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    print(elements)
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    # running test cases
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    tests = [
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        [89, 78, 61, 23, 21, 53, 12, 1, 2, 6, 3, 17, 9],
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        [],
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        [1, 2, 3, 4, 5],
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        [350, 3, 1, 99, 12, 78, 12, 1200],
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        [9]
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    ]
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    # print("Tests case testing...")
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    for elements in tests:
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        SelectionSort(elements)
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        print(elements)
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