c语言vigenere密码_C和C ++中的Vigenere密码

浅浅的花香味﹌ 2022-12-08 04:47 193阅读 0赞

![4b8c4a37a15670e7a77338555c318274.png][]

c语言vigenere密码

In this tutorial you will learn about vigenere cipher in C and C++ for encryption and decryption.

在本教程中，您将学习C和C ++中用于加密和解密的vigenere密码。

Vigenere Cipher is kind of polyalphabetic substitution method. It is used for encryption of alphabetic text. For encryption and decryption Vigenere Cipher Table is used in which alphabets from A to Z are written in 26 rows.

Vigenere密码是一种多字母替换方法。 它用于加密字母文本。 为了进行加密和解密，使用了Vigenere密码表，其中从A到Z的字母写在26行中。

![Vigenere Cipher Table][]

**Also Read: [Caesar Cipher in C and C++ \[Encryption & Decryption\]][Caesar Cipher in C and C_ _Encryption _ Decryption]**

**另请阅读： [C和C ++中的Caesar密码\[加密和解密\]][Caesar Cipher in C and C_ _Encryption _ Decryption]**

**Also Read: [Hill Cipher in C and C++ (Encryption and Decryption)][Hill Cipher in C and C_ _Encryption and Decryption]**

**另请阅读： [C和C ++中的Hill Cipher(加密和解密)][Hill Cipher in C and C_ _Encryption and Decryption]**

### Vigenere密码加密 **(**Vigenere Cipher Encryption**)** ###

**Message Text:** THECRAZYPROGRAMMER

**消息文本：** THECRAZYPROGRAMMER

**Key: **HELLO

**钥匙：** HELLO

Here we have to obtain a new key by repeating the given key till its length become equal to original message length.

在这里，我们必须通过重复给定密钥直到其长度等于原始消息长度来获得新密钥。

**New Generated Key:** HELLOHELLOHELLOHEL

**新生成的密钥：** HELLOHELLOHELLOHEL

For encryption take first letter of message and new key i.e. T and H. Take the alphabet in Vigenere Cipher Table where T row and H column coincides i.e. A.

对于加密，请使用消息的首字母和新密钥，即T和H。在Vigenere密码表中使用字母，其中T行和H列重合，即A。

Repeat the same process for all remaining alphabets in message text. Finally the encrypted message text is:

对消息文本中的所有剩余字母重复相同的过程。 最后，加密的消息文本为：

**Encrypted Message:** ALPNFHDJAFVKCLATIC

**加密的消息：** ALPNFHDJAFVKCLATIC

The algorithm can be expressed in algebraic form as given below. The cipher text can be generated by below equation.

该算法可以以代数形式表示，如下所示。 密文可以通过以下等式生成。

**Ei = (Pi \+ Ki) mod 26**

**E i =(P i \+ K i )mod 26**

Here P is plain text and K is key.

这里P是纯文本，K是密钥。

### Vigenere密码解密 **(**Vigenere Cipher Decryption**)** ###

**Encrypted Message:** ALPNFHDJAFVKCLATIC

**加密的消息：** ALPNFHDJAFVKCLATIC

**Key: **HELLO

**钥匙：** HELLO

**New Generated Key:** HELLOHELLOHELLOHEL

**新生成的密钥：** HELLOHELLOHELLOHEL

Take first alphabet of encrypted message and generated key i.e. A and H. Analyze Vigenere Cipher Table, look for alphabet A in column H, the corresponding row will be the first alphabet of original message i.e. T.

取加密消息的第一个字母和生成的密钥，即A和H。分析Vigenere密码表，在H列中查找字母A，相应的行将是原始消息的第一个字母，即T。

Repeat the same process for all the alphabets in encrypted message.

对加密消息中的所有字母重复相同的过程。

**Original Message:** THECRAZYPROGRAMMER

**原始消息：** THECRAZYPROGRAMMER

Above process can be represented in algebraic form by following equation.

上述过程可以通过以下等式以代数形式表示。

**Pi = (Ei – Ki + 26) mod 26**

**i** ** ** **=(E i – K i \+ 26)mod 26**

We will use above algebraic equations in the program.

我们将在程序中使用上述代数方程。

## Vigenere密码程序 **(**Program for Vigenere Cipher in C**)** ##

#include<stdio.h>
    #include<string.h>
     
    int main(){
        char msg[] = "THECRAZYPROGRAMMER";
        char key[] = "HELLO";
        int msgLen = strlen(msg), keyLen = strlen(key), i, j;
     
        char newKey[msgLen], encryptedMsg[msgLen], decryptedMsg[msgLen];
     
        //generating new key
        for(i = 0, j = 0; i < msgLen; ++i, ++j){
            if(j == keyLen)
                j = 0;
     
            newKey[i] = key[j];
        }
     
        newKey[i] = '\0';
     
        //encryption
        for(i = 0; i < msgLen; ++i)
            encryptedMsg[i] = ((msg[i] + newKey[i]) % 26) + 'A';
     
        encryptedMsg[i] = '\0';
     
        //decryption
        for(i = 0; i < msgLen; ++i)
            decryptedMsg[i] = (((encryptedMsg[i] - newKey[i]) + 26) % 26) + 'A';
     
        decryptedMsg[i] = '\0';
     
        printf("Original Message: %s", msg);
        printf("\nKey: %s", key);
        printf("\nNew Generated Key: %s", newKey);
        printf("\nEncrypted Message: %s", encryptedMsg);
        printf("\nDecrypted Message: %s", decryptedMsg);
     
    	return 0;
    }

**Output**

**输出量**

*Original Message: THECRAZYPROGRAMMER* *Key: HELLO* *New Generated Key: HELLOHELLOHELLOHEL* *Encrypted Message: ALPNFHDJAFVKCLATIC* *Decrypted Message: THECRAZYPROGRAMMER*

*原始消息：THECRAZYPROGRAMMER* *密钥：HELLO* *新生成的密钥：HELLOHELLOHELLOHEL* *加密消息：ALPNFHDJAFVKCLATIC* *解密消息：THECRAZYPROGRAMMER*

## C ++中的Vigenere密码程序 **(**Program for Vigenere Cipher in C++**)** ##

#include<iostream>
    #include<string.h>
     
    using namespace std;
     
    int main(){
        char msg[] = "THECRAZYPROGRAMMER";
        char key[] = "HELLO";
        int msgLen = strlen(msg), keyLen = strlen(key), i, j;
     
        char newKey[msgLen], encryptedMsg[msgLen], decryptedMsg[msgLen];
     
        //generating new key
        for(i = 0, j = 0; i < msgLen; ++i, ++j){
            if(j == keyLen)
                j = 0;
     
            newKey[i] = key[j];
        }
     
        newKey[i] = '\0';
     
        //encryption
        for(i = 0; i < msgLen; ++i)
            encryptedMsg[i] = ((msg[i] + newKey[i]) % 26) + 'A';
     
        encryptedMsg[i] = '\0';
     
        //decryption
        for(i = 0; i < msgLen; ++i)
            decryptedMsg[i] = (((encryptedMsg[i] - newKey[i]) + 26) % 26) + 'A';
     
        decryptedMsg[i] = '\0';
     
        cout<<"Original Message: "<<msg;
        cout<<"\nKey: "<<key;
        cout<<"\nNew Generated Key: "<<newKey;
        cout<<"\nEncrypted Message: "<<encryptedMsg;
        cout<<"\nDecrypted Message: "<<decryptedMsg;
     
    	return 0;
    }

Comment below if you have queries or found anything incorrect in above tutorial for vigenere cipher in C and C++.

如果您有疑问或在上述教程中对C和C ++中的vigenere密码有任何不正确的地方，请在下面评论。

> 翻译自: [https://www.thecrazyprogrammer.com/2017/08/vigenere-cipher-c-c.html][https_www.thecrazyprogrammer.com_2017_08_vigenere-cipher-c-c.html]

c语言vigenere密码

[4b8c4a37a15670e7a77338555c318274.png]: /images/20221123/ce85f8e2c0ce4fc1aa67e039fea5e261.png
[Vigenere Cipher Table]: https://www.thecrazyprogrammer.com/wp-content/uploads/2017/08/Vigenere-Cipher-Table.png
[Caesar Cipher in C and C_ _Encryption _ Decryption]: https://www.thecrazyprogrammer.com/2016/11/caesar-cipher-c-c-encryption-decryption.html
[Hill Cipher in C and C_ _Encryption and Decryption]: https://www.thecrazyprogrammer.com/2017/02/hill-cipher-c.html
[https_www.thecrazyprogrammer.com_2017_08_vigenere-cipher-c-c.html]: https://www.thecrazyprogrammer.com/2017/08/vigenere-cipher-c-c.html