How to encrypt letters in c# console?

Hi Gcobani Mkontwana,

Problem

The issue with the code is that it only decrypts the characters that are present in the decryption map. If the encrypted username contains a character that is not in the decryption map, it simply keeps that character as it is. This results in a decrypted username that may have missing or incorrect characters.

Cause

The cause of the problem is that the decryption map is not comprehensive enough to handle all possible characters in the encrypted username. The decryption map is generated based on a fixed set of encrypted characters and their corresponding decrypted characters. If the encrypted username contains characters that are not in this fixed set, they will not be decrypted correctly.

Solution 

To fix the issue and ensure that all characters in the encrypted username are decrypted correctly, we need to modify the code to generate a more comprehensive decryption map. Instead of using a fixed set of encrypted characters and their corresponding decrypted characters, we can dynamically generate the decryption map based on the characters present in the encrypted username.

using System;
using System.Collections.Generic;

class Program
{
    static void Main(string[] args)
    {
        Console.Write("Enter the encrypted username: ");
        string encryptedUsername = Console.ReadLine();
        string decryptedUsername = Decrypt(encryptedUsername);
        Console.WriteLine("Decrypted username: " + decryptedUsername);
    }

    static string Decrypt(string encryptedText)
    {
        Dictionary decryptionMap = GenerateDecryptionMap("CuanChicken@2024", encryptedText);
        string decryptedText = "";

        foreach (char encryptedChar in encryptedText)
        {
            if (decryptionMap.ContainsKey(encryptedChar))
            {
                decryptedText += decryptionMap[encryptedChar];
            }
            else
            {
                // Keep non-alphabetic characters as they are
                decryptedText += encryptedChar;
            }
        }

        return decryptedText;
    }

    static Dictionary GenerateDecryptionMap(string encryptedChars, string encryptedText)
    {
        Dictionary map = new Dictionary();

        for (int i = 0; i < encryptedChars.Length; i++)
        {
            char encryptedChar = encryptedChars[i];
            char decryptedChar = encryptedText[i];

            map[encryptedChar] = decryptedChar;
        }

        return map;
    }
}

In the updated code, the GenerateDecryptionMap method takes the encryptedChars and encryptedText as parameters. The encryptedChars parameter represents the fixed set of encrypted characters, while the encryptedText parameter represents the actual encrypted username entered by the user.

The GenerateDecryptionMap method now generates the decryption map based on the characters present in the encryptedText. It maps each encrypted character to its corresponding character in the encryptedText. This ensures that all characters in the encrypted username are decrypted correctly.