Add some cool queue, stacks, strings, math, bit manipulation examples (#35)

arrays_and_strings/README.md

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+## arrays and strings
+
+<br>
+
+### `is_palindrome.py`
+
+<br>
+
+```python
+python3 is_palindrome.py
+
+Testing is_palindrome()...
+Is subi no onibus a palindrone?: True
+Is helllo there a palindrone?: False
+```
+
+<br>
+
+### `playing_with_strings.py`
+
+<br>
+
+```python
+python3 playing_with_strings.py
+
+Testing reverse_array_in_place
+Array: [1, 2, 3, 4, 5]
+Reversed: [5, 4, 3, 2, 1]
+```
+
+<br>
+
+### `anagram.py`
+
+<br>
+
+```python
+python3 anagram.py
+
+Testing is_anagram()...
+Is listen an anagram of silent?: True
+```
+
+<br>
+
+### `permutation.py`
+
+<br>
+
+```python
+python3 permutation.py
+
+Testing permutation()...
+Permutation of bt3gl: ['bt3gl', 'bt3lg', 'btg3l', 'btgl3', 'btl3g', 'btlg3', 'b3tgl', 'b3tlg', 'b3gtl', 'b3glt', 'b3ltg', 'b3lgt', 'bgt3l', 'bgtl3', 'bg3tl', 'bg3lt', 'bglt3', 'bgl3t', 'blt3g', 'bltg3', 'bl3tg', 'bl3gt', 'blgt3', 'blg3t', 'tb3gl', 'tb3lg', 'tbg3l', 'tbgl3', 'tbl3g', 'tblg3', 't3bgl', 't3blg', 't3gbl', 't3glb', 't3lbg', 't3lgb', 'tgb3l', 'tgbl3', 'tg3bl', 'tg3lb', 'tglb3', 'tgl3b', 'tlb3g', 'tlbg3', 'tl3bg', 'tl3gb', 'tlgb3', 'tlg3b', '3btgl', '3btlg', '3bgtl', '3bglt', '3bltg', '3blgt', '3tbgl', '3tblg', '3tgbl', '3tglb', '3tlbg', '3tlgb', '3gbtl', '3gblt', '3gtbl', '3gtlb', '3glbt', '3gltb', '3lbtg', '3lbgt', '3ltbg', '3ltgb', '3lgbt', '3lgtb', 'gbt3l', 'gbtl3', 'gb3tl', 'gb3lt', 'gblt3', 'gbl3t', 'gtb3l', 'gtbl3', 'gt3bl', 'gt3lb', 'gtlb3', 'gtl3b', 'g3btl', 'g3blt', 'g3tbl', 'g3tlb', 'g3lbt', 'g3ltb', 'glbt3', 'glb3t', 'gltb3', 'glt3b', 'gl3bt', 'gl3tb', 'lbt3g', 'lbtg3', 'lb3tg', 'lb3gt', 'lbgt3', 'lbg3t', 'ltb3g', 'ltbg3', 'lt3bg', 'lt3gb', 'ltgb3', 'ltg3b', 'l3btg', 'l3bgt', 'l3tbg', 'l3tgb', 'l3gbt', 'l3gtb', 'lgbt3', 'lgb3t', 'lgtb3', 'lgt3b', 'lg3bt', 'lg3tb']
+```

arrays_and_strings/anagram.py

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+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+
+def is_anagram(string1, string2) -> bool:
+
+    string1 = string1.lower()
+    string2 = string2.lower()
+
+    if len(string1) != len(string2):
+        return False
+
+    for char in string1:
+        if char not in string2:
+            return False
+    
+    return True
+
+
+if __name__ == '__main__':
+    
+    print('Testing is_anagram()...')
+    string1 = "listen"
+    string2 = "silent"
+    print(f'Is {string1} an anagram of {string2}?: {is_anagram(string1, string2)}')

arrays_and_strings/palindrome.py

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+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+def is_palindrome(sentence):
+
+    sentence = sentence.strip(' ')
+    if len(sentence) < 2:
+        return True
+    
+    if sentence[0] == sentence[-1]:
+        return is_palindrome(sentence[1:-1])
+    
+    return False
+
+
+if __name__ == '__main__':
+    print('Testing is_palindrome()...')
+    sentence ="subi no onibus"
+    print(f'Is {sentence} a palindrone?: {is_palindrome(sentence)}')
+
+    sentence ="helllo there"
+    print(f'Is {sentence} a palindrone?: {is_palindrome(sentence)}')

arrays_and_strings/permutation.py

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+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+
+def permutation(string) -> list:
+
+    if len(string) == 1:
+        return [string]
+    
+    result = []
+    for i, char in enumerate(string):
+        for perm in permutation(string[:i] + string[i+1:]):
+            result += [char + perm]
+    
+    return result
+
+
+if __name__ == '__main__':
+    print('Testing permutation()...')
+    string = "bt3gl"
+    print(f'Permutation of {string}: {permutation(string)}')

arrays_and_strings/playing_with_strings.py

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+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+def reverse_array_in_place(array):
+    """ Reverse an array in place """
+    return array[::-1]
+
+
+if __name__ == '__main__':
+
+    print('Testing reverse_array_in_place')
+    array = [1, 2, 3, 4, 5]
+    print(f'Array: {array}')
+    print(f'Reversed: {reverse_array_in_place(array)}')