Porta cipher

.github/workflows/directory_writer.yml

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+# The objective of this GitHub Action is to add a new DIRECTORY.md file to a pull request if needed.
+name: directory_writer
+on: [pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      max-parallel: 1
+      matrix:
+        python-version: [3.7]
+    steps:
+
+      - uses: actions/checkout@v1
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v1
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Update DIRECTORY.md
+        run: |
+          scripts/build_directory_md.py 2>&1 | tee DIRECTORY.md
+          git config --global user.name 'directory_writer'
+          git config --global user.email '[email protected]'
+          git remote set-url origin https://x-access-token:${{ secrets.gh_token }}@github.com/$GITHUB_REPOSITORY
+          git checkout $GITHUB_HEAD_REF
+          if git diff-files --quiet; then echo 0; else git commit -am "fixup: DIRECTORY.md" && git push; fi

ciphers/porta_cipher.py

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+alphabet = {
+    "A": ("ABCDEFGHIJKLM", "NOPQRSTUVWXYZ"),
+    "B": ("ABCDEFGHIJKLM", "NOPQRSTUVWXYZ"),
+    "C": ("ABCDEFGHIJKLM", "ZNOPQRSTUVWXY"),
+    "D": ("ABCDEFGHIJKLM", "ZNOPQRSTUVWXY"),
+    "E": ("ABCDEFGHIJKLM", "YZNOPQRSTUVWX"),
+    "F": ("ABCDEFGHIJKLM", "YZNOPQRSTUVWX"),
+    "G": ("ABCDEFGHIJKLM", "XYZNOPQRSTUVW"),
+    "H": ("ABCDEFGHIJKLM", "XYZNOPQRSTUVW"),
+    "I": ("ABCDEFGHIJKLM", "WXYZNOPQRSTUV"),
+    "J": ("ABCDEFGHIJKLM", "WXYZNOPQRSTUV"),
+    "K": ("ABCDEFGHIJKLM", "VWXYZNOPQRSTU"),
+    "L": ("ABCDEFGHIJKLM", "VWXYZNOPQRSTU"),
+    "M": ("ABCDEFGHIJKLM", "UVWXYZNOPQRST"),
+    "N": ("ABCDEFGHIJKLM", "UVWXYZNOPQRST"),
+    "O": ("ABCDEFGHIJKLM", "TUVWXYZNOPQRS"),
+    "P": ("ABCDEFGHIJKLM", "TUVWXYZNOPQRS"),
+    "Q": ("ABCDEFGHIJKLM", "STUVWXYZNOPQR"),
+    "R": ("ABCDEFGHIJKLM", "STUVWXYZNOPQR"),
+    "S": ("ABCDEFGHIJKLM", "RSTUVWXYZNOPQ"),
+    "T": ("ABCDEFGHIJKLM", "RSTUVWXYZNOPQ"),
+    "U": ("ABCDEFGHIJKLM", "QRSTUVWXYZNOP"),
+    "V": ("ABCDEFGHIJKLM", "QRSTUVWXYZNOP"),
+    "W": ("ABCDEFGHIJKLM", "PQRSTUVWXYZNO"),
+    "X": ("ABCDEFGHIJKLM", "PQRSTUVWXYZNO"),
+    "Y": ("ABCDEFGHIJKLM", "OPQRSTUVWXYZN"),
+    "Z": ("ABCDEFGHIJKLM", "OPQRSTUVWXYZN"),
+}
+
+
+def generate_table(key):
+    """
+      >>> generate_table('marvin')
+      [('ABCDEFGHIJKLM', 'UVWXYZNOPQRST'), ('ABCDEFGHIJKLM', 'NOPQRSTUVWXYZ'), ('ABCDEFGHIJKLM', 'STUVWXYZNOPQR'), ('ABCDEFGHIJKLM', 'QRSTUVWXYZNOP'), ('ABCDEFGHIJKLM', 'WXYZNOPQRSTUV'), ('ABCDEFGHIJKLM', 'UVWXYZNOPQRST')]
+      """
+    return [alphabet[char] for char in key.upper()]
+
+
+def encrypt(key, words):
+    """
+      >>> encrypt('marvin', 'jessica')
+      'QRACRWU'
+      """
+    cipher = ""
+    count = 0
+    table = generate_table(key)
+    for char in words.upper():
+        cipher += get_opponent(table[count], char)
+        count = (count + 1) % len(table)
+    return cipher
+
+
+def decrypt(key, words):
+    """
+      >>> decrypt('marvin', 'QRACRWU')
+      'JESSICA'
+      """
+    return encrypt(key, words)
+
+
+def get_position(table, char):
+    """
+      >>> table = [('ABCDEFGHIJKLM', 'UVWXYZNOPQRST'), ('ABCDEFGHIJKLM', 'NOPQRSTUVWXYZ'), ('ABCDEFGHIJKLM', 'STUVWXYZNOPQR'), ('ABCDEFGHIJKLM', 'QRSTUVWXYZNOP'), ('ABCDEFGHIJKLM', 'WXYZNOPQRSTUV'), ('ABCDEFGHIJKLM', 'UVWXYZNOPQRST')]
+      >>> get_position(table, 'A')
+      (None, None)
+      """
+    row = -1
+
+    if char in table[0]:
+        row = 0
+    elif char in table[1]:
+        row = 1
+
+    return (None, None) if row == -1 else (row, table[row].index(char))
+
+
+def get_opponent(table, char):
+    """
+      >>> table = [('ABCDEFGHIJKLM', 'UVWXYZNOPQRST'), ('ABCDEFGHIJKLM', 'NOPQRSTUVWXYZ'), ('ABCDEFGHIJKLM', 'STUVWXYZNOPQR'), ('ABCDEFGHIJKLM', 'QRSTUVWXYZNOP'), ('ABCDEFGHIJKLM', 'WXYZNOPQRSTUV'), ('ABCDEFGHIJKLM', 'UVWXYZNOPQRST')]
+      >>> get_opponent(table, 'A')
+      'A'
+      """
+    row, col = get_position(table, char.upper())
+
+    if row == 1:
+        return table[0][col]
+    else:
+        return table[1][col] if row == 0 else char
+
+
+if __name__ == "__main__":
+    """
+      ENTER KEY: marvin
+      ENTER TEXT TO ENCRYPT: jessica
+      ENCRYPTED: QRACRWU
+      DECRYPTED WITH KEY: JESSICA
+      """
+    key = input("ENTER KEY: ")
+    text = input("ENTER TEXT TO ENCRYPT: ")
+    cipher_text = encrypt(key, text)
+
+    print("ENCRYPTED: " + cipher_text)
+    print("DECRYPTED WITH KEY: " + decrypt(key, cipher_text))
+
+    import doctest
+
+    doctest.testmod()