1 files changed, 49 insertions, 0 deletions
diff --git a/challenge-286/ulrich-rieke/cpp/ch-2.cpp b/challenge-286/ulrich-rieke/cpp/ch-2.cpp
new file mode 100755
index 0000000000..7b1579b314
--- /dev/null
+++ b/challenge-286/ulrich-rieke/cpp/ch-2.cpp
@@ -0,0 +1,49 @@
+#include <iostream>
+#include <vector>
+#include <sstream>
+#include <utility>
+#include <numeric>
+
+//routine for splitting a string at a given delimiter
+std::vector<std::string> split( const std::string & text , const char 
+      delimiter ) {
+   std::vector<std::string> tokens ;
+   std::istringstream istr { text } ;
+   std::string word ;
+   while ( std::getline( istr, word , delimiter )) {
+      tokens.push_back( word ) ;
+   }
+   return tokens ;
+}
+
+int main( ) {
+   std::cout << "Enter 2 ^ n integers, where n is a positive integer!\n" ;
+   std::string line ;
+   std::getline( std::cin , line ) ;
+   auto tokens = split( line , ' ' ) ;
+   std::vector<int> numbers ;
+   for ( auto s : tokens ) 
+      numbers.push_back( std::stoi( s ) ) ;
+   bool last_was_min = false ;//did we determine the minimum last time ?
+   while ( numbers.size( ) > 1 ) {
+      std::vector<std::pair<int , int>> allPairs ;// all neighbouring pairs
+      for ( int i = 0 ; i < numbers.size( ) - 1 ; i += 2 ) {
+	 allPairs.push_back( std::make_pair( numbers[i] , numbers[i + 1] )) ;
+      }
+      std::vector<int> intermediate ; //for the minima and maxima
+      for ( auto it = allPairs.begin( ) ; it != allPairs.end( ) ; it++ ) {
+	 if ( last_was_min ) {
+	    intermediate.push_back( std::max( it->first , it->second ) ) ;
+	    last_was_min = false ; //toggle the boolean value 
+	 }
+	 else {
+	    intermediate.push_back( std::min( it->first , it->second ) ) ;
+	    last_was_min = true ;
+	 }
+      }
+      numbers = intermediate ;
+      intermediate.clear( ) ;
+   }
+   std::cout << *numbers.begin( ) << '\n' ;
+   return 0 ;
+}