Java implements the Virginia encryption/decryption algorithm

Last Update:2018-12-07 Source: Internet

Author: User

Tags key string

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EncryptionAlgorithmProgram:

Public class MTOC
{

// Enter the plaintext and key, and use the entered key to encrypt the plaintext.
Public static void main (string [] ARGs)
{Int I;
Char [] C = new char [100];
Char [] k1 = new char [100];

// Input
System. Out. Print ("enter a mingwen string :");
String M = myinput. readstring ();
System. Out. Print ("enter a key string :");
String K = myinput. readstring ();

// Construct a key table

For (I = 0; I <K. Length (); I ++)
{
If (K. charat (I)> = 'A' & K. charat (I) <= 'Z ')
K1 [I] = (char) (K. charat (I)-97 );
If (K. charat (I)> = 'A' & K. charat (I) <= 'Z ')
K1 [I] = (char) (K. charat (I)-65 );
}

// Encryption

For (I = 0; I <M. Length (); I ++)
{
If (M. charat (I)> = 'A' & M. charat (I) <= 'Z ')
C [I] = (char) (M. charat (I)-97 + K1 [I % K. Length ()]) % 26 + 97 );
If (M. charat (I)> = 'A' & M. charat (I) <= 'Z ')
C [I] = (char) (M. charat (I)-65 + K1 [I % K. Length ()]) % 26 + 65 );
}

// Output ciphertext
For (I = 0; I <C. length; I ++)
System. Out. Print (C [I]);}

}

Decryption algorithm program:

Public class ctom
{

// Enter the password and key, and use the key to decrypt the ciphertext
Public static void main (string [] ARGs)
{Int I;
Char [] M = new char [100];
Char [] k1 = new char [100];

// Input
System. Out. Print ("Enter the miwen string :");
String c = myinput. readstring ();
System. Out. Print ("Enter the key string :");
String K = myinput. readstring ();

// Construct a key table
For (I = 0; I <K. Length (); I ++)
{
If (K. charat (I)> = 'A' & K. charat (I) <= 'Z ')
K1 [I] = (char) (K. charat (I)-97 );
If (K. charat (I)> = 'A' & K. charat (I) <= 'Z ')
K1 [I] = (char) (K. charat (I)-65 );
}

// Decrypt

For (I = 0; I <C. Length (); I ++)
{
If (C. charat (I)> = 'A' & C. charat (I) <= 'Z ')
M [I] = (char) (C. charat (I)-97-k1 [I % K. Length ()] + 26) % 26 + 97 );
If (C. charat (I)> = 'A' & C. charat (I) <= 'Z ')
M [I] = (char) (C. charat (I)-65-k1 [I % K. Length ()] + 26) % 26 + 65 );
}

// Output plaintext
For (I = 0; I <M. length; I ++)
System. Out. Print (M [I]);}

}

Myinput. Java class:

// Myinput. Java: contain the methods for reading int, double, and
// String values from the keyboard
Import java. Io .*;

Public class myinput
{
// Read a string from the keyboard
Public static string readstring ()
{
Bufferedreader br
= New bufferedreader (New inputstreamreader (system. In), 1 );

// Declare and initialize the string
String string = "";

// Get the string from the keyboard
Try
{
String = Br. Readline ();
}
Catch (ioexception ex)
{
System. Out. println (Ex );
}

// Return the string obtained from the keyboard
Return string;
}

// Read an int value from the keyboard
Public static int readint ()
{
Return integer. parseint (readstring ());
}

// Read a double value from the keyboard
Public static double readdouble ()
{
Return double. parsedouble (readstring ());
}

// Read a byte value from the keyboard
Public static byte readbyte ()
{
Return byte. parsebyte (readstring ());
}

// Read a short value from the keyboard
Public static short readshort ()
{
Return short. parseshort (readstring ());
}

// Read a long value from the keyboard
Public static long readlong ()
{
Return long. parselong (readstring ());
}

// Read a float value from the keyboard
Public static float readfloat ()
{
Return float. parsefloat (readstring ());
}
}

Encryption Algorithm Program: