 Console.WriteLine("Epsilon: " + epsilon_b64);
  Console.WriteLine("B64 Decoded: " + BitConverter.ToString(epsilon).Replace("-", ""));
  Console.WriteLine("To String: " + Encoding.UTF8.GetString(epsilon));
  Console.WriteLine();
  
  var decrypted = crypto.Decrypt(epsilon, testkey0, md5);
  Console.WriteLine("Trying Key: " + BitConverter.ToString(testkey0).Replace("-", "") + "   IV: " + BitConverter.ToString(md5).Replace("-", ""));
  Console.WriteLine("Decrypted: " + BitConverter.ToString(decrypted).Replace("-", ""));
  Console.WriteLine("To String" + Encoding.UTF8.GetString(decrypted));
  Console.WriteLine();
  
  decrypted = crypto.Decrypt(epsilon, testkey1, md5);
  Console.WriteLine("Trying Key: " + BitConverter.ToString(testkey1).Replace("-", "") + "   IV: " + BitConverter.ToString(md5).Replace("-", ""));
  Console.WriteLine("Decrypted: " + BitConverter.ToString(decrypted).Replace("-", ""));
  Console.WriteLine("To String" + Encoding.UTF8.GetString(decrypted));  
  Console.WriteLine();
  
  decrypted = crypto.Decrypt(epsilon, testkey2, md5);
  Console.WriteLine("Trying Key: " + BitConverter.ToString(testkey2).Replace("-", "") + "   IV: " + BitConverter.ToString(md5).Replace("-", ""));
  Console.WriteLine("Decrypted: " + BitConverter.ToString(decrypted).Replace("-", ""));
  Console.WriteLine("To String" + Encoding.UTF8.GetString(decrypted));  
  Console.WriteLine();
  
  
  Console.WriteLine();
  Console.WriteLine();
  
 }
 
 public static byte[] HexStringToByteArray(String hex)
 {
  int NumberChars = hex.Length;
  byte[] bytes = new byte[NumberChars / 2];
  for (int i = 0; i < NumberChars; i += 2)
   bytes[i / 2] = Convert.ToByte(hex.Substring(i, 2), 16);
  return bytes;
 }
}

public class AesCryptographyService
{
    public byte[] Encrypt(byte[] data, byte[] key, byte[] iv)
    {
        using (var aes = Aes.Create())
        {
            aes.KeySize = 128;
            aes.BlockSize = 128;
            aes.Padding = PaddingMode.Zeros;

            aes.Key = key;
            aes.IV = iv;

            using (var encryptor = aes.CreateEncryptor(aes.Key, aes.IV))
            {
                return PerformCryptography(data, encryptor);
            }
        }
    }

    public byte[] Decrypt(byte[] data, byte[] key, byte[] iv)
    {
        using (var aes = Aes.Create())
        {
            aes.KeySize = 128;
            aes.BlockSize = 128;
            aes.Padding = PaddingMode.Zeros;

            aes.Key = key;
            aes.IV = iv;

            using (var decryptor = aes.CreateDecryptor(aes.Key, aes.IV))
            {
                return PerformCryptography(data, decryptor);
            }
        }
    }

    private byte[] PerformCryptography(byte[] data, ICryptoTransform cryptoTransform)
    {
        using (var ms = new MemoryStream())
        using (var cryptoStream = new CryptoStream(ms, cryptoTransform, CryptoStreamMode.Write))
        {
            cryptoStream.Write(data, 0, data.Length);
            cryptoStream.FlushFinalBlock();

            return ms.ToArray();
        }
    }
 
 
}

created 3 years ago by Ian S

C++ Online Compiler

Write, Run & Share C++ code online using OneCompiler's C++ online compiler for free. It's one of the robust, feature-rich online compilers for C++ language, running on the latest version 17. Getting started with the OneCompiler's C++ compiler is simple and pretty fast. The editor shows sample boilerplate code when you choose language as C++ and start coding!

Read inputs from stdin

OneCompiler's C++ online compiler supports stdin and users can give inputs to programs using the STDIN textbox under the I/O tab. Following is a sample program which takes name as input and print your name with hello.

#include <iostream>
#include <string>
using namespace std;

int main() 
{
    string name;
    cout << "Enter name:";
    getline (cin, name);
    cout << "Hello " << name;
    return 0;
}

About C++

C++ is a widely used middle-level programming language.

Supports different platforms like Windows, various Linux flavours, MacOS etc
C++ supports OOPS concepts like Inheritance, Polymorphism, Encapsulation and Abstraction.
Case-sensitive
C++ is a compiler based language
C++ supports structured programming language
C++ provides alot of inbuilt functions and also supports dynamic memory allocation.
Like C, C++ also allows you to play with memory using Pointers.

Syntax help

Loops

1. If-Else:

When ever you want to perform a set of operations based on a condition If-Else is used.

if(conditional-expression) {
   //code
}
else {
   //code
}

You can also use if-else for nested Ifs and If-Else-If ladder when multiple conditions are to be performed on a single variable.

2. Switch:

Switch is an alternative to If-Else-If ladder.

switch(conditional-expression){    
case value1:    
 // code    
 break;  // optional  
case value2:    
 // code    
 break;  // optional  
......    
    
default:     
 code to be executed when all the above cases are not matched;    
}

3. For:

For loop is used to iterate a set of statements based on a condition.

for(Initialization; Condition; Increment/decrement){  
  //code  
}

4. While:

While is also used to iterate a set of statements based on a condition. Usually while is preferred when number of iterations are not known in advance.

while (condition) {  
// code 
}

5. Do-While:

Do-while is also used to iterate a set of statements based on a condition. It is mostly used when you need to execute the statements atleast once.

do {  
 // code 
} while (condition);

Functions

Function is a sub-routine which contains set of statements. Usually functions are written when multiple calls are required to same set of statements which increases re-usuability and modularity. Function gets run only when it is called.

How to declare a Function:

return_type function_name(parameters);

How to call a Function:

function_name (parameters)

How to define a Function:

return_type function_name(parameters) {  
 // code
}