Merge pull request #8 from SergeyTsaplin/full-refactoring

Sortings and searching algorithms refactoring

.gitignore

@@ -0,0 +1,90 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+env/
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+*.egg-info/
+.installed.cfg
+*.egg
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*,cover
+.hypothesis/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+target/
+
+# IPython Notebook
+.ipynb_checkpoints
+
+# pyenv
+.python-version
+
+# celery beat schedule file
+celerybeat-schedule
+
+# dotenv
+.env
+
+# virtualenv
+venv/
+ENV/
+
+# Spyder project settings
+.spyderproject
+
+# Rope project settings
+.ropeproject
+.idea

BubbleSort.py

@@ -1,39 +0,0 @@
-import sys
-
-
-def simple_bubble_sort(int_list):
-    count = len(int_list)
-    swapped = True
-    while (swapped):
-        swapped = False
-        for j in range(count - 1):
-            if (int_list[j] > int_list[j + 1]):
-                int_list[j], int_list[j + 1] = int_list[j + 1], int_list[j]
-                swapped = True
-    return int_list
-
-
-def main():
-    # Python 2's `raw_input` has been renamed to `input` in Python 3
-    if sys.version_info.major < 3:
-        input_function = raw_input
-    else:
-        input_function = input
-
-    try:
-        print("Enter numbers separated by spaces:")
-        s = input_function()
-        inputs = list(map(int, s.split(' ')))
-        if len(inputs) < 2:
-            print('No Enough values to sort!')
-            raise Exception
-
-    except Exception as e:
-        print(e)
-    else:
-        sorted_input = simple_bubble_sort(inputs)
-        print('\nSorted list (min to max): {}'.format(sorted_input))
-
-if __name__ == '__main__':
-    print('==== Bubble Sort ====\n')
-    main()

InsertionSort.py

@@ -1,40 +0,0 @@
-import sys
-
-
-def simple_insertion_sort(int_list):
-    count = len(int_list)
-    for i in range(1, count):
-        temp = int_list[i]
-        j = i - 1
-        while(j >= 0 and temp < int_list[j]):
-            int_list[j + 1] = int_list[j]
-            j -= 1
-        int_list[j + 1] = temp
-
-    return int_list
-
-
-def main():
-    # Python 2's `raw_input` has been renamed to `input` in Python 3
-    if sys.version_info.major < 3:
-        input_function = raw_input
-    else:
-        input_function = input
-
-    try:
-        print("Enter numbers separated by spaces:")
-        s = input_function()
-        inputs = list(map(int, s.split(' ')))
-        if len(inputs) < 2:
-            print('No Enough values to sort!')
-            raise Exception
-
-    except Exception as e:
-        print(e)
-    else:
-        sorted_input = simple_insertion_sort(inputs)
-        print('\nSorted list (min to max): {}'.format(sorted_input))
-
-if __name__ == '__main__':
-    print('==== Insertion Sort ====\n')
-    main()

LinearSearch.py

@@ -1,32 +0,0 @@
-import sys
-
-
-def sequential_search(alist, target):
-    for index, item in enumerate(alist):
-        if item == target:
-            print("Found target {} at index {}".format(target, index))
-            break
-    else:
-        print("Not found")
-
-
-def main():
-    # Python 2's `raw_input` has been renamed to `input` in Python 3
-    if sys.version_info.major < 3:
-        input_function = raw_input
-    else:
-        input_function = input
-
-    try:
-        print("Enter numbers separated by spaces")
-        s = input_function()
-        inputs = list(map(int, s.split(' ')))
-        target = int(input_function('\nEnter a number to be found in list: '))
-    except Exception as e:
-        print(e)
-    else:
-        sequential_search(inputs, target)
-
-if __name__ == '__main__':
-    print('==== Linear Search ====\n')
-    main()

MergeSort.py

@@ -1,59 +0,0 @@
-import sys
-
-
-def merge_sort(alist):
-    print("Splitting ", alist)
-    if len(alist) > 1:
-        mid = len(alist) // 2
-        left_half = alist[:mid]
-        right_half = alist[mid:]
-        merge_sort(left_half)
-        merge_sort(right_half)
-        i = j = k = 0
-
-        while i < len(left_half) and j < len(right_half):
-            if left_half[i] < right_half[j]:
-                alist[k] = left_half[i]
-                i += 1
-            else:
-                alist[k] = right_half[j]
-                j += 1
-            k += 1
-
-        while i < len(left_half):
-            alist[k] = left_half[i]
-            i += 1
-            k += 1
-
-        while j < len(right_half):
-            alist[k] = right_half[j]
-            j += 1
-            k += 1
-    print("Merging ", alist)
-    return alist
-
-
-def main():
-    # Python 2's `raw_input` has been renamed to `input` in Python 3
-    if sys.version_info.major < 3:
-        input_function = raw_input
-    else:
-        input_function = input
-
-    try:
-        print("Enter numbers separated by spaces:")
-        s = input_function()
-        inputs = list(map(int, s.split(' ')))
-        if len(inputs) < 2:
-            print('No Enough values to sort!')
-            raise Exception
-
-    except Exception as e:
-        print(e)
-    else:
-        sorted_input = merge_sort(inputs)
-        print('\nSorted list (min to max): {}'.format(sorted_input))
-
-if __name__ == '__main__':
-    print('==== Merge Sort ====\n')
-    main()

QuickSort.py

@@ -1,41 +0,0 @@
-import sys
-
-
-def quick_sort(A, p, r):
-    if p < r:
-        q = partition(A, p, r)
-        quick_sort(A, p, q - 1)
-        quick_sort(A, q + 1, r)
-    return A
-
-
-def partition(A, p, r):
-    i = p - 1
-    for j in range(p, r):
-        if A[j] <= A[r]:
-            i += 1
-            A[i], A[j] = A[j], A[i]
-    A[i + 1], A[r] = A[r], A[i + 1]
-    return i + 1
-
-
-def main():
-    # Python 2's `raw_input` has been renamed to `input` in Python 3
-    if sys.version_info.major < 3:
-        input_function = raw_input
-    else:
-        input_function = input
-
-    try:
-        print("Enter numbers separated by spaces")
-        s = input_function()
-        inputs = list(map(int, s.split(' ')))
-    except Exception as e:
-        print(e)
-    else:
-        sorted_input = quick_sort(inputs, 0, len(inputs) - 1)
-        print('\nSorted list (min to max): {}'.format(sorted_input))
-
-if __name__ == '__main__':
-    print('==== Quick Sort ====\n')
-    main()

binary_seach.py

@@ -2,9 +2,9 @@
 This is pure python implementation of binary search algorithm
 
 For doctests run following command:
-python -m doctest -v selection_sort.py
+python -m doctest -v binary_search.py
 or
-python3 -m doctest -v selection_sort.py
+python3 -m doctest -v binary_search.py
 
 For manual testing run:
 python binary_search.py
@@ -13,30 +13,12 @@ from __future__ import print_function
 import bisect
 
 
-def assert_sorted(collection):
-    """Check if collection is sorted. If not raises :py:class:`ValueError`
-
-    :param collection: collection
-    :return: True if collection is sorted
-    :raise: :py:class:`ValueError` if collection is not sorted
-
-    Examples:
-    >>> assert_sorted([0, 1, 2, 4])
-    True
-
-    >>> assert_sorted([10, -1, 5])
-    Traceback (most recent call last):
-    ...
-    ValueError: Collection must be sorted
-    """
-    if collection != sorted(collection):
-        raise ValueError('Collection must be sorted')
-    return True
-
-
 def binary_search(sorted_collection, item):
     """Pure implementation of binary search algorithm in Python
 
+    Be careful collection must be sorted, otherwise result will be
+    unpredictable
+
     :param sorted_collection: some sorted collection with comparable items
     :param item: item value to search
     :return: index of found item or None if item is not found
@@ -53,12 +35,7 @@ def binary_search(sorted_collection, item):
 
     >>> binary_search([0, 5, 7, 10, 15], 6)
 
-    >>> binary_search([5, 2, 1, 5], 2)
-    Traceback (most recent call last):
-    ...
-    ValueError: Collection must be sorted
     """
-    assert_sorted(sorted_collection)
     left = 0
     right = len(sorted_collection) - 1
 
@@ -78,6 +55,9 @@ def binary_search(sorted_collection, item):
 def binary_search_std_lib(sorted_collection, item):
     """Pure implementation of binary search algorithm in Python using stdlib
 
+    Be careful collection must be sorted, otherwise result will be
+    unpredictable
+
     :param sorted_collection: some sorted collection with comparable items
     :param item: item value to search
     :return: index of found item or None if item is not found
@@ -94,18 +74,34 @@ def binary_search_std_lib(sorted_collection, item):
 
     >>> binary_search_std_lib([0, 5, 7, 10, 15], 6)
 
-    >>> binary_search_std_lib([5, 2, 1, 5], 2)
-    Traceback (most recent call last):
-    ...
-    ValueError: Collection must be sorted
     """
-    assert_sorted(sorted_collection)
     index = bisect.bisect_left(sorted_collection, item)
     if index != len(sorted_collection) and sorted_collection[index] == item:
         return index
     return None
 
 
+def __assert_sorted(collection):
+    """Check if collection is sorted, if not - raises :py:class:`ValueError`
+
+    :param collection: collection
+    :return: True if collection is sorted
+    :raise: :py:class:`ValueError` if collection is not sorted
+
+    Examples:
+    >>> __assert_sorted([0, 1, 2, 4])
+    True
+
+    >>> __assert_sorted([10, -1, 5])
+    Traceback (most recent call last):
+    ...
+    ValueError: Collection must be sorted
+    """
+    if collection != sorted(collection):
+        raise ValueError('Collection must be sorted')
+    return True
+
+
 if __name__ == '__main__':
     import sys
     # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
@@ -117,6 +113,10 @@ if __name__ == '__main__':
 
     user_input = input_function('Enter numbers separated by coma:\n')
     collection = [int(item) for item in user_input.split(',')]
+    try:
+        __assert_sorted(collection)
+    except ValueError:
+        sys.exit('Sequence must be sorted to apply binary search')
 
     target_input = input_function(
         'Enter a single number to be found in the list:\n'

bubble_sort.py

@@ -0,0 +1,52 @@
+"""
+This is pure python implementation of bubble sort algorithm
+
+For doctests run following command:
+python -m doctest -v bubble_sort.py
+or
+python3 -m doctest -v bubble_sort.py
+
+For manual testing run:
+python bubble_sort.py
+"""
+from __future__ import print_function
+
+
+def bubble_sort(collection):
+    """Pure implementation of bubble sort algorithm in Python
+
+    :param collection: some mutable ordered collection with heterogeneous
+    comparable items inside
+    :return: the same collection ordered by ascending
+
+    Examples:
+    >>> bubble_sort([0, 5, 3, 2, 2])
+    [0, 2, 2, 3, 5]
+
+    >>> bubble_sort([])
+    []
+
+    >>> bubble_sort([-2, -5, -45])
+    [-45, -5, -2]
+    """
+    length = len(collection)
+    for i in range(length):
+        for j in range(length-1):
+            if collection[j] > collection[j+1]:
+                collection[j], collection[j+1] = collection[j+1], collection[j]
+
+    return collection
+
+
+if __name__ == '__main__':
+    import sys
+    # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
+    # otherwise 2.x's input builtin function is too "smart"
+    if sys.version_info.major < 3:
+        input_function = raw_input
+    else:
+        input_function = input
+
+    user_input = input_function('Enter numbers separated by coma:\n')
+    unsorted = [int(item) for item in user_input.split(',')]
+    print(bubble_sort(unsorted))

insertion_sort.py

@@ -0,0 +1,56 @@
+"""
+This is pure python implementation of insertion sort algorithm
+
+For doctests run following command:
+python -m doctest -v insertion_sort.py
+or
+python3 -m doctest -v insertion_sort.py
+
+For manual testing run:
+python insertion_sort.py
+"""
+from __future__ import print_function
+
+
+def insertion_sort(collection):
+    """Pure implementation of insertion sort algorithm in Python
+
+    :param collection: some mutable ordered collection with heterogeneous
+    comparable items inside
+    :return: the same collection ordered by ascending
+
+    Examples:
+    >>> insertion_sort([0, 5, 3, 2, 2])
+    [0, 2, 2, 3, 5]
+
+    >>> insertion_sort([])
+    []
+
+    >>> insertion_sort([-2, -5, -45])
+    [-45, -5, -2]
+    """
+    length = len(collection)
+    for i in range(length):
+        current_item = collection[i]
+        j = i - 1
+        while j >= 0 and current_item < collection[j]:
+            collection[j+1] = collection[j]
+            j -= 1
+        collection[j+1] = current_item
+
+    return collection
+
+
+if __name__ == '__main__':
+    import sys
+
+    # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
+    # otherwise 2.x's input builtin function is too "smart"
+    if sys.version_info.major < 3:
+        input_function = raw_input
+    else:
+        input_function = input
+
+    user_input = input_function('Enter numbers separated by coma:\n')
+    unsorted = [int(item) for item in user_input.split(',')]
+    print(insertion_sort(unsorted))

linear_search.py

@@ -0,0 +1,62 @@
+"""
+This is pure python implementation of linear search algorithm
+
+For doctests run following command:
+python -m doctest -v linear_search.py
+or
+python3 -m doctest -v linear_search.py
+
+For manual testing run:
+python linear_search.py
+"""
+from __future__ import print_function
+
+
+def linear_search(sequence, target):
+    """Pure implementation of binary search algorithm in Python
+
+    :param sequence: some sorted collection with comparable items
+    :param target: item value to search
+    :return: index of found item or None if item is not found
+
+    Examples:
+    >>> linear_search([0, 5, 7, 10, 15], 0)
+    0
+
+    >>> linear_search([0, 5, 7, 10, 15], 15)
+    4
+
+    >>> linear_search([0, 5, 7, 10, 15], 5)
+    1
+
+    >>> linear_search([0, 5, 7, 10, 15], 6)
+
+    """
+    for index, item in enumerate(sequence):
+        if item == target:
+            return index
+    return None
+
+
+if __name__ == '__main__':
+    import sys
+
+    # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
+    # otherwise 2.x's input builtin function is too "smart"
+    if sys.version_info.major < 3:
+        input_function = raw_input
+    else:
+        input_function = input
+
+    user_input = input_function('Enter numbers separated by coma:\n')
+    sequence = [int(item) for item in user_input.split(',')]
+
+    target_input = input_function(
+        'Enter a single number to be found in the list:\n'
+    )
+    target = int(target_input)
+    result = linear_search(sequence, target)
+    if result is not None:
+        print('{} found at positions: {}'.format(target, result))
+    else:
+        print('Not found')

merge_sort.py

@@ -0,0 +1,76 @@
+"""
+This is pure python implementation of merge sort algorithm
+
+For doctests run following command:
+python -m doctest -v merge_sort.py
+or
+python3 -m doctest -v merge_sort.py
+
+For manual testing run:
+python merge_sort.py
+"""
+from __future__ import print_function
+
+
+def merge_sort(collection):
+    """Pure implementation of merge sort algorithm in Python
+
+    :param collection: some mutable ordered collection with heterogeneous
+    comparable items inside
+    :return: the same collection ordered by ascending
+
+    Examples:
+    >>> merge_sort([0, 5, 3, 2, 2])
+    [0, 2, 2, 3, 5]
+
+    >>> merge_sort([])
+    []
+
+    >>> merge_sort([-2, -5, -45])
+    [-45, -5, -2]
+    """
+    length = len(collection)
+    if length > 1:
+        midpoint = length // 2
+        left_half = merge_sort(collection[:midpoint])
+        right_half = merge_sort(collection[midpoint:])
+        i = 0
+        j = 0
+        k = 0
+        left_length = len(left_half)
+        right_length = len(right_half)
+        while i < left_length and j < right_length:
+            if left_half[i] < right_half[j]:
+                collection[k] = left_half[i]
+                i += 1
+            else:
+                collection[k] = right_half[j]
+                j += 1
+            k += 1
+
+        while i < left_length:
+            collection[k] = left_half[i]
+            i += 1
+            k += 1
+
+        while j < right_length:
+            collection[k] = right_half[j]
+            j += 1
+            k += 1
+
+    return collection
+
+
+if __name__ == '__main__':
+    import sys
+
+    # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
+    # otherwise 2.x's input builtin function is too "smart"
+    if sys.version_info.major < 3:
+        input_function = raw_input
+    else:
+        input_function = input
+
+    user_input = input_function('Enter numbers separated by coma:\n')
+    unsorted = [int(item) for item in user_input.split(',')]
+    print(merge_sort(unsorted))

quick_sort.py

@@ -0,0 +1,61 @@
+"""
+This is pure python implementation of quick sort algorithm
+
+For doctests run following command:
+python -m doctest -v quick_sort.py
+or
+python3 -m doctest -v quick_sort.py
+
+For manual testing run:
+python quick_sort.py
+"""
+from __future__ import print_function
+
+
+def quick_sort(collection):
+    """Pure implementation of quick sort algorithm in Python
+
+    :param collection: some mutable ordered collection with heterogeneous
+    comparable items inside
+    :return: the same collection ordered by ascending
+
+    Examples:
+    >>> quick_sort([0, 5, 3, 2, 2])
+    [0, 2, 2, 3, 5]
+
+    >>> quick_sort([])
+    []
+
+    >>> quick_sort([-2, -5, -45])
+    [-45, -5, -2]
+    """
+    less = []
+    equal = []
+    greater = []
+    if len(collection) > 1:
+        pivot = collection[0]
+        for x in collection:
+            if x < pivot:
+                less.append(x)
+            if x == pivot:
+                equal.append(x)
+            if x > pivot:
+                greater.append(x)
+        return quick_sort(less) + equal + quick_sort(greater)
+    else:
+        return collection
+
+
+if __name__ == '__main__':
+    import sys
+
+    # For python 2.x and 3.x compatibility: 3.x has not raw_input builtin
+    # otherwise 2.x's input builtin function is too "smart"
+    if sys.version_info.major < 3:
+        input_function = raw_input
+    else:
+        input_function = input
+
+    user_input = input_function('Enter numbers separated by coma:\n')
+    unsorted = [int(item) for item in user_input.split(',')]
+    print(quick_sort(unsorted))

selection_sort.py

@@ -5,10 +5,14 @@ For doctests run following command:
 python -m doctest -v selection_sort.py
 or
 python3 -m doctest -v selection_sort.py
+
+For manual testing run:
+python selection_sort.py
 """
 from __future__ import print_function
 
-def selection_sort(sortable):
+
+def selection_sort(collection):
     """Pure implementation of selection sort algorithm in Python
 
     Examples:
@@ -21,20 +25,20 @@ def selection_sort(sortable):
     >>> selection_sort([-2, -5, -45])
     [-45, -5, -2]
 
-    :param sortable: some mutable ordered collection with heterogeneous
+    :param collection: some mutable ordered collection with heterogeneous
     comparable items inside
     :return: the same collection ordered by ascending
     """
-    length = len(sortable)
+    length = len(collection)
     for i in range(length):
         least = i
         for k in range(i + 1, length):
-            if sortable[k] < sortable[least]:
+            if collection[k] < collection[least]:
                 least = k
-        sortable[least], sortable[i] = (
+        collection[least], collection[i] = (
-            sortable[i], sortable[least]
+            collection[i], collection[least]
         )
-    return sortable
+    return collection
 
 
 if __name__ == '__main__':