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diff --git a/challenge-281/ulrich-rieke/cpp/ch-2.cpp b/challenge-281/ulrich-rieke/cpp/ch-2.cpp
new file mode 100755
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+++ b/challenge-281/ulrich-rieke/cpp/ch-2.cpp
@@ -0,0 +1,80 @@
+#include <iostream>
+#include <vector>
+#include <string>
+#include <map>
+#include <sstream>
+#include <cstdlib>
+#include <algorithm>
+
+std::vector<std::string> split( const std::string & text , char delimiter ) {
+   std::istringstream istr { text } ;
+   std::string word ;
+   std::vector<std::string> words ;
+   while ( std::getline( istr , word , delimiter ) ) {
+      words.push_back( word ) ;
+   }
+   return words ;
+}
+
+//create all fields of a chess board
+std::vector<std::string> findAllFields( ) {
+   std::string cols {"abcdefgh"} ;
+   std::string rows {"12345678"} ;
+   std::vector<std::string> board ;
+   for ( int i = 0 ; i < cols.length( ) ; i++ ) {
+      for ( int j = 0 ; j < rows.length( ) ; j++ ) {
+	 std::string field { cols.substr( i , 1 ).append( rows.substr( j , 1 ) ) } ;
+	 board.push_back( field ) ;
+      }
+   }
+   return board ;
+}
+
+//all suitable fields on a chessboard are those that differ from the given field
+// by an absolute difference of 2 in rows and of 1 in columns or vice versa
+std::vector<std::string> findTargets( const std::string & field , const 
+      std::vector<std::string> & board ) {
+   std::vector<std::string> selected ;
+   static const std::string columns {"abcdefgh"} ;
+   static const std::string rows {"12345678"} ;
+   auto selector = [field]( const auto & f ) {
+      auto colfound = columns.find_first_of( field.substr( 0 , 1 ) ) ;
+      auto rowfound = rows.find_first_of( field.substr( 1 , 1 ) ) ;
+      auto fieldcol = columns.find_first_of( f.substr( 0 , 1 ) ) ;
+      auto fieldrow = rows.find_first_of( f.substr( 1 , 1 ) ) ;
+      auto coldiff = abs( colfound - fieldcol ) ;
+      auto rowdiff = abs( rowfound - fieldrow ) ;
+      return ( (coldiff == 1) && (rowdiff == 2)) || ( (coldiff == 2) &&
+	    (rowdiff == 1 )) ;
+   } ;
+   std::copy_if( board.begin( ) , board.end( ) , std::back_inserter( selected ) , 
+	 selector ) ;
+   return selected ;
+}
+
+int main( ) {
+   std::cout << "Enter a source and a target field!\n" ;
+   std::string line ;
+   std::getline( std::cin, line ) ;
+   std::vector<std::string> fields { split( line , ' ' ) } ;
+   std::vector<std::string> chessboard { findAllFields( ) } ;
+   std::string sourceField { fields[ 0 ] } ;
+   std::string targetField { fields[ 1 ] } ;
+   std::vector<std::string> targets = findTargets( sourceField , chessboard ) ;
+   int count = 1 ;
+   while ( std::find( targets.begin( ) , targets.end( ) , targetField ) == 
+	 targets.end( ) ) {
+      count++ ;
+      std::vector<std::string> newTargets , elementTargets  ;
+      for ( auto it = targets.begin( ) ; it != targets.end( ) ; it++ ) {
+	 elementTargets = findTargets( *it , chessboard ) ;
+	 for ( auto f : elementTargets ) 
+	    newTargets.push_back( f ) ;
+	 elementTargets.clear( ) ;
+      }
+      for ( auto f : newTargets ) 
+	 targets.push_back( f ) ;
+   }
+   std::cout << count << '\n' ;
+   return 0 ;
+}