编写Python代码实现Vigenere 密码算法和Hill密码算法

Vigenère密码是一种简单的替换式加密技术，通过将明文和密钥按字符周期交替组合来达到加密目的。下面是一个简单的 Python 示例，展示了如何使用 Vigenère密码进行加密：

def vigenere_encrypt(plaintext, key):
    key_length = len(key)
    encrypted_text = ""
    for i in range(len(plaintext)):
        char = plaintext[i]
        if char.isalpha():
            shift = ord(key[i % key_length].upper()) - ord('A')
            shifted_char = chr(((ord(char.upper()) - ord('A') + shift) % 26) + ord('A'))
            if char.islower():
                encrypted_text += shifted_char.lower()
            else:
                encrypted_text += shifted_char
        else:
            encrypted_text += char
    return encrypted_text

# 示例用法
plaintext = "Hello, World!"
key = "KEY"
encrypted = vigenere_encrypt(plaintext, key)
print(f"Encrypted text: {encrypted}")

至于 Hill密码，这是一种基于矩阵运算的块加密算法，用于加密固定长度的字符块（如3x3字母）。由于涉及到矩阵操作，需要更复杂的数学处理。以下是 Hill密码加密的一个基础示例：

import numpy as np

def rotate_matrix(matrix, shift):
    n = matrix.shape[0]
    result = [[0] * n for _ in range(n)]
    for i in range(n):
        for j in range(n):
            result[(i + shift) % n][(j + shift) % n] = matrix[i][j]
    return result

def multiply_matrices(matrix1, matrix2):
    result = np.zeros((matrix1.shape[0], matrix2.shape[1]), dtype=int)
    for i in range(result.shape[0]):
        for j in range(result.shape[1]):
            for k in range(matrix1.shape[1]):
                result[i][j] += (matrix1[i][k] * matrix2[k][j])
    return result % 26

def hill_cipher_encrypt(text_blocks, key_matrix):
    encrypted_blocks = []
    for block in text_blocks:
        # 字符转数字（小写字母）
        block_num = [ord(c.lower()) - ord('a') for c in block]
        
        # 将字符块扩展到矩阵大小，如果不足填充0
        if len(block_num) < key_matrix.shape[0]:
            pad = [(0, 0)] * ((key_matrix.shape[0] - len(block_num)) // 2) + [(len(block_num), 0)]
            block_num.extend([pad[i][0] for i in range(len(pad))])
            
        encrypted_block_num = multiply_matrices(np.array(block_num).reshape(key_matrix.shape), key_matrix)
        encrypted_block = ''.join(chr(i + ord('a')) for i in encrypted_block_num.reshape(-1))
        encrypted_blocks.append(encrypted_block)

    return encrypted_blocks

# 示例用法
text = "Example text to encrypt"
key = "KRYPTOS"
key_matrix = generate_key_matrix(key)  # 实现生成一个合适的密钥矩阵

blocks = chunks(text, 3)  # 分割成3x3的字符块
encrypted_blocks = hill_cipher_encrypt(blocks, key_matrix)

注意，实际应用中你需要实现 `generate_key_matrix` 函数来生成适合的密钥矩阵，并确保文本块的分割、填充和矩阵乘法规则正确。