Data update

Task/Bifid-cipher/C-sharp/bifid-cipher.cs

@@ -0,0 +1,130 @@
+using System;
+using System.Collections.Generic;
+using System.Drawing;
+
+public class BifidCipher
+{
+    public static void Main(string[] args)
+    {
+        string message1 = "ATTACKATDAWN";
+        string message2 = "FLEEATONCE";
+        string message3 = "The invasion will start on the first of January".ToUpper().Replace(" ", "");
+
+        Bifid bifid1 = new Bifid(5, "ABCDEFGHIKLMNOPQRSTUVWXYZ");
+        Bifid bifid2 = new Bifid(5, "BGWKZQPNDSIOAXEFCLUMTHYVR");
+
+        RunTest(bifid1, message1);
+        RunTest(bifid2, message2);
+        RunTest(bifid2, message1);
+        RunTest(bifid1, message2);
+
+        Bifid bifid3 = new Bifid(6, "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789");
+        RunTest(bifid3, message3);
+    }
+
+    private static void RunTest(Bifid bifid, string message)
+    {
+        Console.WriteLine("Using Polybius square:");
+        bifid.Display();
+        Console.WriteLine("Message:   " + message);
+        string encrypted = bifid.Encrypt(message);
+        Console.WriteLine("Encrypted: " + encrypted);
+        string decrypted = bifid.Decrypt(encrypted);
+        Console.WriteLine("Decrypted: " + decrypted);
+        Console.WriteLine();
+    }
+}
+
+public class Bifid
+{
+    private char[,] grid;
+    private Dictionary<char, Point> coordinates = new Dictionary<char, Point>();
+
+    public Bifid(int n, string text)
+    {
+        if (text.Length != n * n)
+        {
+            throw new ArgumentException("Incorrect length of text");
+        }
+
+        grid = new char[n, n];
+        int row = 0;
+        int col = 0;
+
+        foreach (char ch in text)
+        {
+            grid[row, col] = ch;
+            coordinates[ch] = new Point(row, col);
+            col += 1;
+            if (col == n)
+            {
+                col = 0;
+                row += 1;
+            }
+        }
+
+        if (n == 5)
+        {
+            coordinates['J'] = coordinates['I'];
+        }
+    }
+
+    public string Encrypt(string text)
+    {
+        List<int> rowOne = new List<int>();
+        List<int> rowTwo = new List<int>();
+
+        foreach (char ch in text)
+        {
+            Point coordinate = coordinates[ch];
+            rowOne.Add(coordinate.X);
+            rowTwo.Add(coordinate.Y);
+        }
+
+        rowOne.AddRange(rowTwo);
+        var result = new System.Text.StringBuilder();
+
+        for (int i = 0; i < rowOne.Count - 1; i += 2)
+        {
+            result.Append(grid[rowOne[i], rowOne[i + 1]]);
+        }
+
+        return result.ToString();
+    }
+
+    public string Decrypt(string text)
+    {
+        List<int> row = new List<int>();
+
+        foreach (char ch in text)
+        {
+            Point coordinate = coordinates[ch];
+            row.Add(coordinate.X);
+            row.Add(coordinate.Y);
+        }
+
+        int middle = row.Count / 2;
+        List<int> rowOne = row.GetRange(0, middle);
+        List<int> rowTwo = row.GetRange(middle, row.Count - middle);
+        var result = new System.Text.StringBuilder();
+
+        for (int i = 0; i < middle; i++)
+        {
+            result.Append(grid[rowOne[i], rowTwo[i]]);
+        }
+
+        return result.ToString();
+    }
+
+    public void Display()
+    {
+        for (int i = 0; i < grid.GetLength(0); i++)
+        {
+            for (int j = 0; j < grid.GetLength(1); j++)
+            {
+                Console.Write(grid[i, j] + " ");
+            }
+            Console.WriteLine();
+        }
+    }
+}

Task/Bifid-cipher/FutureBasic/bifid-cipher.basic

@@ -0,0 +1,62 @@
+clear local fn recode( t as CFStringRef, code as CFStringRef ) as CFStringRef
+  CFStringRef s = @""
+  Short i, k, w = sqr( len( code ) )
+
+  for i = 0 to len( t ) - 1 step 2
+    k = intval( mid( t, i, 2 ) ) // Get ‘coordinates’ of char in code string
+    k = w * ( k / 10 ) + k mod 10
+    s = fn StringByAppendingString( s, mid( code, k, 1 ) )
+  next
+
+end fn = s
+
+//
+
+clear local fn encode( s as CFStringRef, code as CFStringRef ) as CFStringRef
+  CFStringRef a = @"", b = @"", c
+  Short i, k, w = sqr( len( code ) )
+  if w == 5 then s = fn StringByReplacingOccurrencesOfString( s, @"J", @"I" )
+  print s
+
+  for i = 0 to len( s ) - 1
+    c = mid( s, i, 1 )
+    k = instr( 0, code, c ) // Put row in one string, column in the other
+    a = fn StringByAppendingString( a, fn StringWithFormat( @"%d", k / w ) )
+    b = fn StringByAppendingString( b, fn StringWithFormat( @"%d", k mod w ) )
+  next
+
+  a = fn StringByAppendingString( a, b ) // Combine the two strings, and recode
+
+end fn = fn recode( a, code )
+
+//
+
+clear local fn decode( s as CFStringRef, code as CFStringRef ) as CFStringRef
+  CFStringRef a = @"", b = @"", c
+  Short i, k, w = sqr( len( code ) )
+
+  for i = 0 to ( len( s ) - 1 )
+    c = mid( s, i, 1 )
+    k = instr( 0, code, c ) // Put row and columm in one long string
+    a = fn StringByAppendingString( a, fn StringWithFormat( @"%d%d", k / w, k mod w ) )
+  next
+
+  for i = 0 to len( a ) / 2 - 1 // Take row from first half of string, column from second
+    c = fn StringByAppendingString( mid( a, i, 1 ), mid( a, i + len( a ) / 2 , 1 ) )
+    b = fn StringByAppendingString( b , c ) // Combine, and recode
+  next
+
+end fn = fn recode( b, code )
+
+//
+
+print fn encode( @"ATTACKATDAWN", @"ABCDEFGHIKLMNOPQRSTUVWXYZ" )
+print fn decode( @"DQBDAXDQPDQH", @"ABCDEFGHIKLMNOPQRSTUVWXYZ" )
+print
+print fn encode( @"FLEEATONCE", @"BGWKZQPDNSIOAXEFCLUMTHYVR" )
+print fn decode( @"UAEOLWRINS", @"BGWKZQPDNSIOAXEFCLUMTHYVR" )
+print
+print fn encode( @"HAPPY40THDAD", @"ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" )
+print fn decode( @"GO31GAGVANJD", @"ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789" )
+
+handleevents