本文概述

• C ++
• Java
• Python3
• C#

Vigenere密码是一种加密字母文本的方法。它使用一种简单的形式多字母替代。多字母密码是任何基于替换的密码, 使用多个替换字母。原始文本的加密使用维吉涅广场或维吉涅桌.

• 该表由在不同行中写出26次的字母组成, 每个字母与上一个字母相比循环向左移动, 对应于26个可能的字母凯撒密码.
• 在加密过程的不同点, 密码使用的密码与行之一不同。
• 在每个点使用的字母取决于重复的关键字。

例子：

Input : Plaintext :lsbinKeyword :AYUSHOutput : Ciphertext :GCYCZFMLYLEIMFor generating key, the given keyword is repeatedin a circular manner until it matches the length of the plain text.The keyword "AYUSH" generates the key "AYUSHAYUSHAYU"The plain text is then encrypted using the process explained below.

加密
明文的第一个字母G与密钥的第一个字母A配对。因此, 请使用Vigenère正方形的G行和A列, 即G。类似地, 对于明文的第二个字母, 使用键的第二个字母, E行和Y列的字母为C。其余的明文以类似的方式被加密。
加密表–极客

文章图片
解密
解密是通过以下步骤进行的：转到表中与密钥对应的行, 找到密文字母在该行中的位置, 然后将该列的标签用作纯文本。例如, 在A行(来自AYUSH)中, 密文G出现在G列中, 这是第一个明文字母。接下来我们转到Y行(来自AYUSH), 找到在E列中找到的密文C, 因此E是第二个明文字母。
更多易于实施通过将[A-Z]转换为数字[0-25], 可以可视化Vigenère代数。

EncryptionThe plaintext(P) and key(K) are added modulo 26.Ei = (Pi + Ki) mod 26DecryptionDi = (Ei - Ki + 26) mod 26

注意：d一世表示明文的第i个字符的偏移量。像偏移一种是0和乙是1, 依此类推。
以下是该想法的实现。
C ++

// C++ code to implement Vigenere Cipher #include< bits/stdc++.h> using namespace std; // This function generates the key in // a cyclic manner until it's length isi'nt // equal to the length of original text string generateKey(string str, string key) { int x = str.size(); for ( int i = 0; ; i++) { if (x == i) i = 0; if (key.size() == str.size()) break ; key.push_back(key[i]); } return key; }// This function returns the encrypted text // generated with the help of the key string cipherText(string str, string key) { string cipher_text; for ( int i = 0; i < str.size(); i++) { // converting in range 0-25 char x = (str[i] + key[i]) %26; // convert into alphabets(ASCII) x += 'A' ; cipher_text.push_back(x); } return cipher_text; }// This function decrypts the encrypted text // and returns the original text string originalText(string cipher_text, string key) { string orig_text; for ( int i = 0 ; i < cipher_text.size(); i++) { // converting in range 0-25 char x = (cipher_text[i] - key[i] + 26) %26; // convert into alphabets(ASCII) x += 'A' ; orig_text.push_back(x); } return orig_text; }// Driver program to test the above function int main() { string str = "lsbin" ; string keyword = "AYUSH" ; string key = generateKey(str, keyword); string cipher_text = cipherText(str, key); cout < < "Ciphertext : " < < cipher_text < < "\n" ; cout < < "Original/Decrypted Text : " < < originalText(cipher_text, key); return 0; }

Java

// Java code to implement Vigenere Cipherclass GFG {// This function generates the key in // a cyclic manner until it's length isi'nt // equal to the length of original text static String generateKey(String str, String key) { int x = str.length(); for ( int i = 0 ; ; i++) { if (x == i) i = 0 ; if (key.length() == str.length()) break ; key+=(key.charAt(i)); } return key; }// This function returns the encrypted text // generated with the help of the key static String cipherText(String str, String key) { String cipher_text= "" ; for ( int i = 0 ; i < str.length(); i++) { // converting in range 0-25 int x = (str.charAt(i) + key.charAt(i)) % 26 ; // convert into alphabets(ASCII) x += 'A' ; cipher_text+=( char )(x); } return cipher_text; }// This function decrypts the encrypted text // and returns the original text static String originalText(String cipher_text, String key) { String orig_text= "" ; for ( int i = 0 ; i < cipher_text.length() & & i < key.length(); i++) { // converting in range 0-25 int x = (cipher_text.charAt(i) - key.charAt(i) + 26 ) % 26 ; // convert into alphabets(ASCII) x += 'A' ; orig_text+=( char )(x); } return orig_text; }// Driver code public static void main(String[] args) { String str = "lsbin" ; String keyword = "AYUSH" ; String key = generateKey(str, keyword); String cipher_text = cipherText(str, key); System.out.println( "Ciphertext : " + cipher_text + "\n" ); System.out.println( "Original/Decrypted Text : " + originalText(cipher_text, key)); } }// This code has been contributed by 29AjayKumar

Python3

# Python code to implement # Vigenere Cipher# This function generates the # key in a cyclic manner until # it's length isn't equal to # the length of original text def generateKey(string, key): key = list (key) if len (string) = = len (key): return (key) else : for i in range ( len (string) - len (key)): key.append(key[i % len (key)]) return ("" . join(key))# This function returns the # encrypted text generated # with the help of the key def cipherText(string, key): cipher_text = [] for i in range ( len (string)): x = ( ord (string[i]) + ord (key[i])) % 26 x + = ord ( 'A' ) cipher_text.append( chr (x)) return ("" . join(cipher_text))# This function decrypts the # encrypted text and returns # the original text def originalText(cipher_text, key): orig_text = [] for i in range ( len (cipher_text)): x = ( ord (cipher_text[i]) - ord (key[i]) + 26 ) % 26 x + = ord ( 'A' ) orig_text.append( chr (x)) return ("" . join(orig_text))# Driver code if __name__ = = "__main__" : string = "lsbin" keyword = "AYUSH" key = generateKey(string, keyword) cipher_text = cipherText(string, key) print ( "Ciphertext :" , cipher_text) print ( "Original/Decrypted Text :" , originalText(cipher_text, key))# This code is contributed # by Pratik Somwanshi

C#

// C# code to implement Vigenere Cipher using System; class GFG {// This function generates the key in // a cyclic manner until it's length isi'nt // equal to the length of original text static String generateKey(String str, String key) { int x = str.Length; for ( int i = 0; ; i++) { if (x == i) i = 0; if (key.Length == str.Length) break ; key+=(key[i]); } return key; }// This function returns the encrypted text // generated with the help of the key static String cipherText(String str, String key) { String cipher_text= "" ; for ( int i = 0; i < str.Length; i++) { // converting in range 0-25 int x = (str[i] + key[i]) %26; // convert into alphabets(ASCII) x += 'A' ; cipher_text+=( char )(x); } return cipher_text; }// This function decrypts the encrypted text // and returns the original text static String originalText(String cipher_text, String key) { String orig_text= "" ; for ( int i = 0 ; i < cipher_text.Length & & i < key.Length; i++) { // converting in range 0-25 int x = (cipher_text[i] - key[i] + 26) %26; // convert into alphabets(ASCII) x += 'A' ; orig_text+=( char )(x); } return orig_text; }// Driver code public static void Main(String[] args) { String str = "lsbin" ; String keyword = "AYUSH" ; String key = generateKey(str, keyword); String cipher_text = cipherText(str, key); Console.WriteLine( "Ciphertext : " + cipher_text + "\n" ); Console.WriteLine( "Original/Decrypted Text : " + originalText(cipher_text, key)); } }/* This code contributed by PrinciRaj1992 */

输出如下：

Ciphertext : GCYCZFMLYLEIMOriginal/Decrypted Text : lsbin

【Vigenere密码解析和代码实现详细指南】参考：https://en.wikipedia.org/wiki/Vigen%C3%A8re_cipher

推荐阅读

• 

  什么是对公负债业务
• 

  做生鲜电商需要办什么营业执照
• 

  威能壁挂炉代码百度如何解决
• 

  拍鸟用什么相机好
• 

  荒野行动物品怎么拆分 如何分开扔掉道具
• 

  黄雅琼个人资料介绍 黄雅琼个人资料介绍
• 

  怎样做稻谷酒
• 

  天山雪菊哪里买 天山雪菊多少钱才能买到
• 

  鹅蛋和什么东西不能吃
• 

  电池容量|骁龙870基本“零差评”，这四款价格两千左右，入手用三年
• 

  mongodb数据库迁移到另一台服务器 mongodb 迁移数据
• 

  紫叶草怎么种植 紫叶草怎么养
• 

  补办车牌号一般几天可以下来
• 

  3m汽车膜分几个档次 汽车贴膜什么牌子好
• 

  前端|实习生 Git 不熟练，还没脸去问是种什么体验
• 

  开发转数据分析,数据分析好还是大数据开发好
• 

  熊童子多肉服盆的注意事项有哪些 多肉熊童子用什么盆好看
• 

  地板出汗怎么办 地板如何去汗，地板如何去汗渍
• 

  冠状沟白色污垢是什么
• 

  mysql中的锁指的是什么 mysql导致锁的原因

• 快速访问数据（散列表（Hash Table）实现原理和代码实例详解）
• 多级队列（MLQ）CPU调度简介
• 回溯算法（N皇后问题解析和多语言代码实现）
• Python MySQL删除查询使用详细指南
• C#类和对象用法详细指南
• JavaScript Math max（）方法使用介绍
• PHP Ds PriorityQueue pop（）函数用法介绍
• PHP | getprotobyname（）函数用法介绍
• C++标准模板库（STL）中的队列用法介绍