homework01 поток 1.2 Новицкая Е.М.

homework01/01допзадание.py

@@ -0,0 +1,33 @@
+def encrypt_poly_shift(plaintext: str, odd_shift: int, even_shift: int) -> str:
+    alphabet = "абвгдежзийклмнопрстуфхцчшщъыьэюя"
+    alphabet_length = len(alphabet)
+
+    encrypted_text = []
+
+    for index, char in enumerate(plaintext):
+        position = index + 1
+
+        if char.lower() in alphabet:
+            shift = odd_shift if position % 2 != 0 else even_shift
+
+            original_index = alphabet.index(char.lower())
+
+            new_index = (original_index + shift) % alphabet_length
+
+            encrypted_char = alphabet[new_index]
+
+            if char.isupper():
+                encrypted_text.append(encrypted_char.upper())
+            else:
+                encrypted_text.append(encrypted_char)
+        else:
+            encrypted_text.append(char)
+
+    return "".join(encrypted_text)
+
+
+plaintext = input()
+odd_shift = int(input())
+even_shift = int(input())
+encrypted = encrypt_poly_shift(plaintext, odd_shift, even_shift)
+print(encrypted)

homework01/caesar.py

@@ -1,6 +1,7 @@
 def encrypt_caesar(plaintext: str, shift: int = 3) -> str:
     """
     Encrypts plaintext using a Caesar cipher.
+
     >>> encrypt_caesar("PYTHON")
     'SBWKRQ'
     >>> encrypt_caesar("python")
@@ -11,13 +12,22 @@ def encrypt_caesar(plaintext: str, shift: int = 3) -> str:
     ''
     """
     ciphertext = ""
-    # PUT YOUR CODE HERE
+    for S in plaintext:
+        if "A" <= S <= "Z":
+            new_s = chr((ord(S) - ord("A") + shift) % 26 + ord("A"))
+            ciphertext += new_s
+        elif "a" <= S <= "z":
+            new_s = chr((ord(S) - ord("a") + shift) % 26 + ord("a"))
+            ciphertext += new_s
+        else:
+            ciphertext += S
     return ciphertext
 
 
 def decrypt_caesar(ciphertext: str, shift: int = 3) -> str:
     """
     Decrypts a ciphertext using a Caesar cipher.
+
     >>> decrypt_caesar("SBWKRQ")
     'PYTHON'
     >>> decrypt_caesar("sbwkrq")
@@ -28,5 +38,18 @@ def decrypt_caesar(ciphertext: str, shift: int = 3) -> str:
     ''
     """
     plaintext = ""
-    # PUT YOUR CODE HERE
-    return plaintext
+    for S in ciphertext:
+        if "A" <= S <= "Z":
+            new_s = chr((ord(S) - ord("A") - shift) % 26 + ord("A"))
+            plaintext += new_s
+        elif "a" <= S <= "z":
+            new_s = chr((ord(S) - ord("a") - shift) % 26 + ord("a"))
+            plaintext += new_s
+        else:
+            plaintext += S
+    return plaintext
+
+
+if __name__ == "__main__":
+    print(encrypt_caesar(input()))
+    print(decrypt_caesar(input()))

homework01/rsa.py

@@ -12,8 +12,17 @@ def is_prime(n: int) -> bool:
     >>> is_prime(8)
     False
     """
-    # PUT YOUR CODE HERE
-    pass
+    count = 0
+    for i in range(2, n - 1):
+        if abs(n) % i == 0:
+            count += 1
+            break
+    if n <= 1:
+        count += 1
+    if count == 0:
+        return True
+    else:
+        return False
 
 
 def gcd(a: int, b: int) -> int:
@@ -24,8 +33,11 @@ def gcd(a: int, b: int) -> int:
     >>> gcd(3, 7)
     1
     """
-    # PUT YOUR CODE HERE
-    pass
+    m = 0
+    for i in range(1, max(a, b) + 1):
+        if a % i == 0 and b % i == 0 and i > m:
+            m = i
+    return m
 
 
 def multiplicative_inverse(e: int, phi: int) -> int:
@@ -35,21 +47,24 @@ def multiplicative_inverse(e: int, phi: int) -> int:
     >>> multiplicative_inverse(7, 40)
     23
     """
-    # PUT YOUR CODE HERE
-    pass
+    d = 1
+    if (e == 1) or (phi == 1):
+        d = 0
+    else:
+        while (d * e) % phi != 1:
+            d += 1
+
+    return d
 
 
 def generate_keypair(p: int, q: int) -> tp.Tuple[tp.Tuple[int, int], tp.Tuple[int, int]]:
     if not (is_prime(p) and is_prime(q)):
         raise ValueError("Both numbers must be prime.")
     elif p == q:
         raise ValueError("p and q cannot be equal")
+    n = p * q
 
-    # n = pq
-    # PUT YOUR CODE HERE
-
-    # phi = (p-1)(q-1)
-    # PUT YOUR CODE HERE
+    phi = (p - 1) * (q - 1)
 
     # Choose an integer e such that e and phi(n) are coprime
     e = random.randrange(1, phi)
@@ -82,7 +97,7 @@ def decrypt(pk: tp.Tuple[int, int], ciphertext: tp.List[int]) -> str:
     # Unpack the key into its components
     key, n = pk
     # Generate the plaintext based on the ciphertext and key using a^b mod m
-    plain = [chr((char ** key) % n) for char in ciphertext]
+    plain = [chr((char**key) % n) for char in ciphertext]
     # Return the array of bytes as a string
     return "".join(plain)
 
@@ -100,4 +115,4 @@ def decrypt(pk: tp.Tuple[int, int], ciphertext: tp.List[int]) -> str:
     print("".join(map(lambda x: str(x), encrypted_msg)))
     print("Decrypting message with public key ", public, " . . .")
     print("Your message is:")
-    print(decrypt(public, encrypted_msg))
+    print(decrypt(public, encrypted_msg))

homework01/vigenere.py

@@ -8,8 +8,37 @@ def encrypt_vigenere(plaintext: str, keyword: str) -> str:
     >>> encrypt_vigenere("ATTACKATDAWN", "LEMON")
     'LXFOPVEFRNHR'
     """
+
+    if len(plaintext) > len(keyword):
+        diff = len(plaintext) - len(keyword)
+        for i in range(diff):
+            keyword += keyword[i]
+    nums = []
     ciphertext = ""
-    # PUT YOUR CODE HERE
+
+    for i in range(len(keyword)):
+        if keyword[i].isalpha():
+            if keyword[i].islower():
+                nums.append((ord(keyword[i]) - ord("a")) % 26)
+            else:
+                nums.append((ord(keyword[i]) - ord("A")) % 26)
+        else:
+            nums.append(0)
+
+    for i in range(len(nums)):
+        if plaintext[i].isalpha():
+            if plaintext[i].islower():
+                if ord(plaintext[i]) + nums[i] <= ord("z"):
+                    ciphertext += chr(ord(plaintext[i]) + nums[i])
+                else:
+                    ciphertext += chr(ord(plaintext[i]) + nums[i] - 26)
+            else:
+                if ord(plaintext[i]) + nums[i] <= ord("Z"):
+                    ciphertext += chr(ord(plaintext[i]) + nums[i])
+                else:
+                    ciphertext += chr(ord(plaintext[i]) + nums[i] - 26)
+        else:
+            ciphertext += plaintext[i]
     return ciphertext
 
 
@@ -23,6 +52,34 @@ def decrypt_vigenere(ciphertext: str, keyword: str) -> str:
     >>> decrypt_vigenere("LXFOPVEFRNHR", "LEMON")
     'ATTACKATDAWN'
     """
+
+    if len(ciphertext) > len(keyword):
+        diff = len(ciphertext) - len(keyword)
+        for i in range(diff):
+            keyword += keyword[i]
+    nums = []
     plaintext = ""
-    # PUT YOUR CODE HERE
-    return plaintext
+    for i in range(len(ciphertext)):
+        if keyword[i].isalpha():
+            if keyword[i].islower():
+                nums.append((ord(keyword[i]) - ord("a")) % 26)
+            else:
+                nums.append((ord(keyword[i]) - ord("A")) % 26)
+        else:
+            nums.append(0)
+
+    for i in range(len(nums)):
+        if ciphertext[i].isalpha():
+            if ciphertext[i].islower():
+                if ord(ciphertext[i]) - nums[i] >= ord("a"):
+                    plaintext += chr(ord(ciphertext[i]) - nums[i])
+                else:
+                    plaintext += chr(ord(ciphertext[i]) - nums[i] + 26)
+            else:
+                if ord(ciphertext[i]) - nums[i] >= ord("A"):
+                    plaintext += chr(ord(ciphertext[i]) - nums[i])
+                else:
+                    plaintext += chr(ord(ciphertext[i]) - nums[i] + 26)
+        else:
+            plaintext += ciphertext[i]
+    return plaintext

homework02/sudoku.py

@@ -5,7 +5,7 @@
 
 
 def read_sudoku(path: tp.Union[str, pathlib.Path]) -> tp.List[tp.List[str]]:
-    """ Прочитать Судоку из указанного файла """
+    """Прочитать Судоку из указанного файла"""
     path = pathlib.Path(path)
     with path.open() as f:
         puzzle = f.read()
@@ -19,15 +19,11 @@ def create_grid(puzzle: str) -> tp.List[tp.List[str]]:
 
 
 def display(grid: tp.List[tp.List[str]]) -> None:
-    """Вывод Судоку """
+    """Вывод Судоку"""
     width = 2
     line = "+".join(["-" * (width * 3)] * 3)
     for row in range(9):
-        print(
-            "".join(
-                grid[row][col].center(width) + ("|" if str(col) in "25" else "") for col in range(9)
-            )
-        )
+        print("".join(grid[row][col].center(width) + ("|" if str(col) in "25" else "") for col in range(9)))
         if str(row) in "25":
             print(line)
     print()
@@ -107,7 +103,7 @@ def find_possible_values(grid: tp.List[tp.List[str]], pos: tp.Tuple[int, int]) -
 
 
 def solve(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.List[tp.List[str]]]:
-    """ Решение пазла, заданного в grid """
+    """Решение пазла, заданного в grid"""
     """ Как решать Судоку?
         1. Найти свободную позицию
         2. Найти все возможные значения, которые могут находиться на этой позиции
@@ -122,7 +118,7 @@ def solve(grid: tp.List[tp.List[str]]) -> tp.Optional[tp.List[tp.List[str]]]:
 
 
 def check_solution(solution: tp.List[tp.List[str]]) -> bool:
-    """ Если решение solution верно, то вернуть True, в противном случае False """
+    """Если решение solution верно, то вернуть True, в противном случае False"""
     # TODO: Add doctests with bad puzzles
     pass
 
@@ -159,4 +155,4 @@ def generate_sudoku(N: int) -> tp.List[tp.List[str]]:
         if not solution:
             print(f"Puzzle {fname} can't be solved")
         else:
-            display(solution)
+            display(solution)

homework02/test_sudoku.py

@@ -239,4 +239,4 @@ def test_generate_sudoku(self):
         self.assertEqual(expected_unknown, actual_unknown)
         solution = sudoku.solve(grid)
         solved = sudoku.check_solution(solution)
-        self.assertTrue(solved)
+        self.assertTrue(solved)