Glede na sporočilo v obliki navadnega besedila in številčni ključ šifrira/dešifrira dano besedilo s pomočjo stolpčne transpozicijske šifre Stolpčna transpozicijska šifra je oblika transpozicijske šifre, tako kot Šifra železniške ograje . Stolpčni prenos vključuje zapisovanje odprtega besedila v vrstice in nato branje šifriranega besedila v stolpcih enega za drugim.

Primeri:

    Encryption     Input : Geeks for Geeks Key = HACK Output : e kefGsGsrekoe_      Decryption     Input : e kefGsGsrekoe_ Key = HACK Output : Geeks for Geeks      Encryption     Input : Geeks on work Key = HACK Output : e w_eoo_Gs kknr_      Decryption     Input : e w_eoo_Gs kknr_ Key = HACK Output : Geeks on work   
    Šifriranje    
 

 
 V transpozicijski šifri se vrstni red abecede preuredi, da se dobi šifrirano besedilo.  
 
 
 Sporočilo je zapisano v vrsticah s fiksno dolžino in nato ponovno prebrano stolpec za stolpcem, stolpci pa so izbrani v nekem kodiranem vrstnem redu.  
 
 Širina vrstic in permutacija stolpcev sta običajno določena s ključno besedo.  
 
 Na primer, beseda HACK je dolžine 4 (torej so vrstice dolžine 4), permutacija pa je določena z abecednim vrstnim redom črk v ključni besedi. V tem primeru bi bil vrstni red '3 1 2 4'.  
 
 Morebitni prosti prostori so zapolnjeni z ničlami ​​ali pa ostanejo prazni ali postavljeni z znakom (primer: _).  
 
 Nazadnje se sporočilo prebere v stolpcih v vrstnem redu, ki ga določa ključna beseda.  
 
   
    Dešifriranje    
 
 
 Za dešifriranje mora prejemnik izračunati dolžine stolpcev tako, da dolžino sporočila deli z dolžino ključa.  
 
 Nato znova napišite sporočilo v stolpce in preuredite stolpce tako, da spremenite ključno besedo.  
 
 C++   
   // CPP program for illustrating   // Columnar Transposition Cipher   #include          using     namespace     std  ;   // Encription function   string     Encryption  (  int     no_rows       int     len_key       int     len_msg        string     msg       int     col_val  [])   {      int     x     =     0  ;      char     enc_mat  [  no_rows     +     1  ][  len_key  ];      // creating the matrix      for     (  int     i     =     0  ;     i      <     no_rows     +     1  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     len_key  ;     j  ++  )     {      // initializes the positions with '_' after the      // end of message      if     (  x     >=     len_msg  )     {      enc_mat  [  i  ][  j  ]     =     '_'  ;      }      else     {      enc_mat  [  i  ][  j  ]     =     msg  [  x  ];      }      x  ++  ;      }      }      int     t     =     1  ;      string     cipher     =     ''  ;      // finding the cipher text according to the value of      // col_val matrix      while     (  t      <=     len_key  )     {      for     (  int     i     =     0  ;     i      <     len_key  ;     i  ++  )     {      int     k     =     col_val  [  i  ];      if     (  k     ==     t  )     {      for     (  int     j     =     0  ;     j      <     no_rows     +     1  ;     j  ++  )     {      cipher     +=     enc_mat  [  j  ][  i  ];      }      t  ++  ;      }      }      }      return     cipher  ;   }   // decryption function   string     Decryption  (  int     no_rows       int     len_key       string     cipher        int     col_val  [])   {      char     dec_mat  [  no_rows     +     1  ][  len_key  ];      int     x     =     0       t     =     1  ;      // rearrange the matrix according to the col_val      while     (  t      <=     len_key  )     {      for     (  int     i     =     0  ;     i      <     len_key  ;     i  ++  )     {      int     k     =     col_val  [  i  ];      if     (  k     ==     t  )     {      for     (  int     j     =     0  ;     j      <     no_rows     +     1  ;     j  ++  )     {      dec_mat  [  j  ][  i  ]     =     cipher  [  x  ];      x  ++  ;      }      t  ++  ;      }      }      }      string     message     =     ''  ;      for     (  int     i     =     0  ;     i      <     no_rows     +     1  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     len_key  ;     j  ++  )     {      // replacing the '_' with space      if     (  dec_mat  [  i  ][  j  ]     ==     '_'  )     {      dec_mat  [  i  ][  j  ]     =     ' '  ;      }      message     +=     dec_mat  [  i  ][  j  ];      }      }      return     message  ;   }   int     main  ()   {      // message      string     msg     =     'Geeks for Geeks'  ;      // key      string     key     =     'HACK'  ;      int     len_key     =     key  .  length  ();      int     len_msg     =     msg  .  length  ();      int     val     =     1       count     =     0       ind  ;      int     col_val  [  len_key  ];      // intializing col_val matrix with 0      memset  (  col_val       0       sizeof  (  col_val  ));      // numbering the key alphabets according to its ACII      // value      while     (  count      <     len_key  )     {      int     min     =     999  ;      for     (  int     i     =     0  ;     i      <     len_key  ;     i  ++  )     {      if     ((  min     >     int  (  key  [  i  ]))     &&     (  col_val  [  i  ]     ==     0  ))     {      min     =     int  (  key  [  i  ]);      ind     =     i  ;      }      }      col_val  [  ind  ]     =     val  ;      count  ++  ;      val  ++  ;      }      int     no_rows     =     len_msg     /     len_key  ;      // encrypted text      string     cipher_text     =     ' '  ;      cipher_text     =     Encryption  (  no_rows       len_key       len_msg       msg        col_val  );      cout      < <     'Encrypted Message : '      < <     cipher_text      < <     endl  ;      // decrypted text      string     original_msg     =     ' '  ;      original_msg     =     Decryption  (  no_rows       len_key       cipher_text        col_val  );      cout      < <     'Decrypted Message : '      < <     original_msg      < <     endl  ;   }   // This code is contributed by Suchita Gond   
  Java   
   import     java.util.*  ;   public     class   ColumnarTranspositionCipher     {      // Key for Columnar Transposition      static     final     String     key     =     'HACK'  ;      static     Map   <  Character       Integer  >     keyMap     =     new     HashMap   <>  ();      static     void     setPermutationOrder  ()     {      // Add the permutation order into the map      for     (  int     i     =     0  ;     i      <     key  .  length  ();     i  ++  )     {      keyMap  .  put  (  key  .  charAt  (  i  )     i  );      }      }      // Encryption      static     String     encryptMessage  (  String     msg  )     {      int     row       col  ;      StringBuilder     cipher     =     new     StringBuilder  ();      /* Calculate the number of columns in the matrix */      col     =     key  .  length  ();      /* Calculate the maximum number of rows in the matrix */      row     =     (  int  )     Math  .  ceil  ((  double  )     msg  .  length  ()     /     col  );      char  [][]     matrix     =     new     char  [  row  ][  col  ]  ;      for     (  int     i     =     0       k     =     0  ;     i      <     row  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     col  ;     )     {      if     (  k      <     msg  .  length  ())     {      char     ch     =     msg  .  charAt  (  k  );      if     (  Character  .  isLetter  (  ch  )     ||     ch     ==     ' '  )     {      matrix  [  i  ][  j  ]     =     ch  ;      j  ++  ;      }      k  ++  ;      }     else     {      /* Add padding character '_' */      matrix  [  i  ][  j  ]     =     '_'  ;      j  ++  ;      }      }      }      for     (  Map  .  Entry   <  Character       Integer  >     entry     :     keyMap  .  entrySet  ())     {      int     columnIndex     =     entry  .  getValue  ();      // Get the cipher text from the matrix column-wise using the permuted key      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      if     (  Character  .  isLetter  (  matrix  [  i  ][  columnIndex  ]  )     ||     matrix  [  i  ][  columnIndex  ]     ==     ' '     ||     matrix  [  i  ][  columnIndex  ]     ==     '_'  )     {      cipher  .  append  (  matrix  [  i  ][  columnIndex  ]  );      }      }      }      return     cipher  .  toString  ();      }      // Decryption      static     String     decryptMessage  (  String     cipher  )     {      /* Calculate the number of columns for the cipher matrix */      int     col     =     key  .  length  ();      int     row     =     (  int  )     Math  .  ceil  ((  double  )     cipher  .  length  ()     /     col  );      char  [][]     cipherMat     =     new     char  [  row  ][  col  ]  ;      /* Add characters into the matrix column-wise */      int     k     =     0  ;      for     (  int     j     =     0  ;     j      <     col  ;     j  ++  )     {      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      cipherMat  [  i  ][  j  ]     =     cipher  .  charAt  (  k  );      k  ++  ;      }      }      /* Update the order of the key for decryption */      int     index     =     0  ;      for     (  Map  .  Entry   <  Character       Integer  >     entry     :     keyMap  .  entrySet  ())     {      entry  .  setValue  (  index  ++  );      }      /* Arrange the matrix column-wise according to the permutation order */      char  [][]     decCipher     =     new     char  [  row  ][  col  ]  ;      for     (  int     l     =     0  ;     l      <     key  .  length  ();     l  ++  )     {      int     columnIndex     =     keyMap  .  get  (  key  .  charAt  (  l  ));      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      decCipher  [  i  ][  l  ]     =     cipherMat  [  i  ][  columnIndex  ]  ;      }      }      /* Get the message using the matrix */      StringBuilder     msg     =     new     StringBuilder  ();      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     col  ;     j  ++  )     {      if     (  decCipher  [  i  ][  j  ]     !=     '_'  )     {      msg  .  append  (  decCipher  [  i  ][  j  ]  );      }      }      }      return     msg  .  toString  ();      }      public     static     void     main  (  String  []     args  )     {      /* Message */      String     msg     =     'Geeks for Geeks'  ;      setPermutationOrder  ();      // Calling encryption function      String     cipher     =     encryptMessage  (  msg  );      System  .  out  .  println  (  'Encrypted Message: '     +     cipher  );      // Calling Decryption function      System  .  out  .  println  (  'Decrypted Message: '     +     decryptMessage  (  cipher  ));      }   }   
  Python   
   # Python3 implementation of   # Columnar Transposition   import   math   key   =   'HACK'   # Encryption   def   encryptMessage  (  msg  ):   cipher   =   ''   # track key indices   k_indx   =   0   msg_len   =   float  (  len  (  msg  ))   msg_lst   =   list  (  msg  )   key_lst   =   sorted  (  list  (  key  ))   # calculate column of the matrix   col   =   len  (  key  )   # calculate maximum row of the matrix   row   =   int  (  math  .  ceil  (  msg_len   /   col  ))   # add the padding character '_' in empty   # the empty cell of the matix   fill_null   =   int  ((  row   *   col  )   -   msg_len  )   msg_lst  .  extend  (  '_'   *   fill_null  )   # create Matrix and insert message and   # padding characters row-wise   matrix   =   [  msg_lst  [  i  :   i   +   col  ]   for   i   in   range  (  0     len  (  msg_lst  )   col  )]   # read matrix column-wise using key   for   _   in   range  (  col  ):   curr_idx   =   key  .  index  (  key_lst  [  k_indx  ])   cipher   +=   ''  .  join  ([  row  [  curr_idx  ]   for   row   in   matrix  ])   k_indx   +=   1   return   cipher   # Decryption   def   decryptMessage  (  cipher  ):   msg   =   ''   # track key indices   k_indx   =   0   # track msg indices   msg_indx   =   0   msg_len   =   float  (  len  (  cipher  ))   msg_lst   =   list  (  cipher  )   # calculate column of the matrix   col   =   len  (  key  )   # calculate maximum row of the matrix   row   =   int  (  math  .  ceil  (  msg_len   /   col  ))   # convert key into list and sort   # alphabetically so we can access   # each character by its alphabetical position.   key_lst   =   sorted  (  list  (  key  ))   # create an empty matrix to   # store deciphered message   dec_cipher   =   []   for   _   in   range  (  row  ):   dec_cipher   +=   [[  None  ]   *   col  ]   # Arrange the matrix column wise according   # to permutation order by adding into new matrix   for   _   in   range  (  col  ):   curr_idx   =   key  .  index  (  key_lst  [  k_indx  ])   for   j   in   range  (  row  ):   dec_cipher  [  j  ][  curr_idx  ]   =   msg_lst  [  msg_indx  ]   msg_indx   +=   1   k_indx   +=   1   # convert decrypted msg matrix into a string   try  :   msg   =   ''  .  join  (  sum  (  dec_cipher     []))   except   TypeError  :   raise   TypeError  (  'This program cannot'     'handle repeating words.'  )   null_count   =   msg  .  count  (  '_'  )   if   null_count   >   0  :   return   msg  [:   -  null_count  ]   return   msg   # Driver Code   msg   =   'Geeks for Geeks'   cipher   =   encryptMessage  (  msg  )   print  (  'Encrypted Message:   {}  '  .   format  (  cipher  ))   print  (  'Decryped Message:   {}  '  .   format  (  decryptMessage  (  cipher  )))   # This code is contributed by Aditya K   
  C#   
   using     System  ;   using     System.Collections.Generic  ;   public     class     ColumnarTranspositionCipher     {      // Key for Columnar Transposition      static     readonly     string     key     =     'HACK'  ;      static     Dictionary   <  char       int  >     keyMap      =     new     Dictionary   <  char       int  >  ();      static     void     SetPermutationOrder  ()      {      // Add the permutation order into the dictionary      for     (  int     i     =     0  ;     i      <     key  .  Length  ;     i  ++  )     {      keyMap  [  key  [  i  ]]     =     i  ;      }      }      // Encryption      static     string     EncryptMessage  (  string     msg  )      {      int     row       col  ;      System  .  Text  .  StringBuilder     cipher      =     new     System  .  Text  .  StringBuilder  ();      /* Calculate the number of columns in the matrix */      col     =     key  .  Length  ;      /* Calculate the maximum number of rows in the    * matrix */      row     =     (  int  )  Math  .  Ceiling  ((  double  )  msg  .  Length     /     col  );      char  [     ]     matrix     =     new     char  [  row       col  ];      for     (  int     i     =     0       k     =     0  ;     i      <     row  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     col  ;)     {      if     (  k      <     msg  .  Length  )     {      char     ch     =     msg  [  k  ];      if     (  char  .  IsLetter  (  ch  )     ||     ch     ==     ' '  )     {      matrix  [  i       j  ]     =     ch  ;      j  ++  ;      }      k  ++  ;      }      else     {      /* Add padding character '_' */      matrix  [  i       j  ]     =     '_'  ;      j  ++  ;      }      }      }      foreach  (      var     entry     in     new     Dictionary   <  char       int  >  (  keyMap  ))      {      int     columnIndex     =     entry  .  Value  ;      // Get the cipher text from the matrix      // column-wise using the permuted key      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      if     (  char  .  IsLetter  (  matrix  [  i       columnIndex  ])      ||     matrix  [  i       columnIndex  ]     ==     ' '      ||     matrix  [  i       columnIndex  ]     ==     '_'  )     {      cipher  .  Append  (  matrix  [  i       columnIndex  ]);      }      }      }      return     cipher  .  ToString  ();      }      // Decryption      static     string     DecryptMessage  (  string     cipher  )      {      /* Calculate the number of columns for the cipher    * matrix */      int     col     =     key  .  Length  ;      int     row     =     (  int  )  Math  .  Ceiling  ((  double  )  cipher  .  Length      /     col  );      char  [     ]     cipherMat     =     new     char  [  row       col  ];      /* Add characters into the matrix column-wise */      int     k     =     0  ;      for     (  int     j     =     0  ;     j      <     col  ;     j  ++  )     {      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      cipherMat  [  i       j  ]     =     cipher  [  k  ];      k  ++  ;      }      }      /* Update the order of the key for decryption */      int     index     =     0  ;      foreach  (      var     entry     in     new     Dictionary   <  char       int  >  (  keyMap  ))      {      keyMap  [  entry  .  Key  ]     =     index  ++  ;      }      /* Arrange the matrix column-wise according to the    * permutation order */      char  [     ]     decCipher     =     new     char  [  row       col  ];      foreach  (  var     entry     in     keyMap  )      {      int     columnIndex     =     entry  .  Value  ;      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      decCipher  [  i       columnIndex  ]      =     cipherMat  [  i       columnIndex  ];      }      }      /* Get the message using the matrix */      System  .  Text  .  StringBuilder     msg      =     new     System  .  Text  .  StringBuilder  ();      for     (  int     i     =     0  ;     i      <     row  ;     i  ++  )     {      for     (  int     j     =     0  ;     j      <     col  ;     j  ++  )     {      if     (  decCipher  [  i       j  ]     !=     '_'  )     {      msg  .  Append  (  decCipher  [  i       j  ]);      }      }      }      return     msg  .  ToString  ();      }      public     static     void     Main  (  string  []     args  )      {      /* Message */      string     msg     =     'Geeks for Geeks'  ;      SetPermutationOrder  ();      // Calling encryption function      string     cipher     =     EncryptMessage  (  msg  );      Console  .  WriteLine  (  'Encrypted Message: '     +     cipher  );      // Calling Decryption function      Console  .  WriteLine  (  'Decrypted Message: '      +     DecryptMessage  (  cipher  ));      }   }   
  JavaScript   
   // JavaScript implementation of    // Columnar Transposition   const     key     =     'HACK'  ;   // Encryption   function     encryptMessage  (  msg  )     {      let     cipher     =     ''  ;      // track key indices      let     k_indx     =     0  ;      const     msg_len     =     msg  .  length  ;      const     msg_lst     =     Array  .  from  (  msg  );      const     key_lst     =     Array  .  from  (  key  ).  sort  ();      // calculate column of the matrix      const     col     =     key  .  length  ;      // calculate maximum row of the matrix      const     row     =     Math  .  ceil  (  msg_len     /     col  );      // add the padding character '_' in empty      // the empty cell of the matrix      const     fill_null     =     (  row     *     col  )     -     msg_len  ;      for     (  let     i     =     0  ;     i      <     fill_null  ;     i  ++  )     {      msg_lst  .  push  (  '_'  );      }      // create Matrix and insert message and      // padding characters row-wise      const     matrix     =     [];      for     (  let     i     =     0  ;     i      <     msg_lst  .  length  ;     i     +=     col  )     {      matrix  .  push  (  msg_lst  .  slice  (  i       i     +     col  ));      }      // read matrix column-wise using key      for     (  let     _     =     0  ;     _      <     col  ;     _  ++  )     {      const     curr_idx     =     key  .  indexOf  (  key_lst  [  k_indx  ]);      for     (  const     row     of     matrix  )     {      cipher     +=     row  [  curr_idx  ];      }      k_indx  ++  ;      }      return     cipher  ;   }   // Decryption   function     decryptMessage  (  cipher  )     {      let     msg     =     ''  ;      // track key indices      let     k_indx     =     0  ;      // track msg indices      let     msg_indx     =     0  ;      const     msg_len     =     cipher  .  length  ;      const     msg_lst     =     Array  .  from  (  cipher  );      // calculate column of the matrix      const     col     =     key  .  length  ;      // calculate maximum row of the matrix      const     row     =     Math  .  ceil  (  msg_len     /     col  );      // convert key into list and sort       // alphabetically so we can access       // each character by its alphabetical position.      const     key_lst     =     Array  .  from  (  key  ).  sort  ();      // create an empty matrix to       // store deciphered message      const     dec_cipher     =     [];      for     (  let     i     =     0  ;     i      <     row  ;     i  ++  )     {      dec_cipher  .  push  (  Array  (  col  ).  fill  (  null  ));      }      // Arrange the matrix column wise according       // to permutation order by adding into a new matrix      for     (  let     _     =     0  ;     _      <     col  ;     _  ++  )     {      const     curr_idx     =     key  .  indexOf  (  key_lst  [  k_indx  ]);      for     (  let     j     =     0  ;     j      <     row  ;     j  ++  )     {      dec_cipher  [  j  ][  curr_idx  ]     =     msg_lst  [  msg_indx  ];      msg_indx  ++  ;      }      k_indx  ++  ;      }      // convert decrypted msg matrix into a string      try     {      msg     =     dec_cipher  .  flat  ().  join  (  ''  );      }     catch     (  err  )     {      throw     new     Error  (  'This program cannot handle repeating words.'  );      }      const     null_count     =     (  msg  .  match  (  /_/g  )     ||     []).  length  ;      if     (  null_count     >     0  )     {      return     msg  .  slice  (  0       -  null_count  );      }      return     msg  ;   }   // Driver Code   const     msg     =     'Geeks for Geeks'  ;   const     cipher     =     encryptMessage  (  msg  );   console  .  log  (  'Encrypted Message: '     +     cipher  );   console  .  log  (  'Decrypted Message: '     +     decryptMessage  (  cipher  ));   // This code is contributed by phasing17   
    
  Izhod   
Encrypted Message : e kefGsGsrekoe_ Decrypted Message : Geeks for Geeks  
 
  
 
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