1 files changed, 40 insertions, 0 deletions
diff --git a/challenge-277/ulrich-rieke/cpp/ch-1.cpp b/challenge-277/ulrich-rieke/cpp/ch-1.cpp
new file mode 100755
index 0000000000..df1d66194e
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+++ b/challenge-277/ulrich-rieke/cpp/ch-1.cpp
@@ -0,0 +1,40 @@
+#include <iostream>
+#include <ranges>
+#include <string>
+#include <vector>
+#include <map>
+#include <algorithm>
+
+std::vector<std::string> split( std::string text , char delim ) {
+   auto parts = text | std::views::split( delim ) 
+                     | std::views::transform( []( auto&& subpart ) {
+			return std::string( subpart.begin( ) ,
+			      subpart.end( ) ) ; }) ;
+   std::vector<std::string> words ( parts.begin( ) , parts.end( ) ) ;
+   return words ;
+}
+
+int main( ) {
+   std::cout << "Enter some words , separated by blanks!\n" ;
+   std::string firstLine , secondLine ;
+   std::getline( std::cin , firstLine ) ;
+   std::cout << "Enter some more words , separated by blanks!\n" ;
+   std::getline( std::cin , secondLine ) ;
+   std::vector<std::string> firstWords( split( firstLine , ' ' ) ) ;
+   std::vector<std::string> secondWords( split( secondLine , ' ' ) ) ;
+   std::vector<std::string> common_words ;
+   std::ranges::sort( firstWords ) ; //intersection only on sorted containers!
+   std::ranges::sort( secondWords ) ;
+   std::set_intersection( firstWords.begin( ) , firstWords.end( ) , 
+	 secondWords.begin( ) , secondWords.end( ) , std::back_inserter( 
+	    common_words ) ) ;
+   std::map<std::string , int> firstFreq , secondFreq ;
+   for ( auto s : firstWords ) 
+      firstFreq[s]++ ;
+   for ( auto s : secondWords ) 
+      secondFreq[s]++ ;
+   std::cout << std::count_if( common_words.begin( ) , common_words.end( ), 
+	 [&firstFreq , &secondFreq]( auto s ){ return firstFreq.find( s )
+	 ->second == 1 && secondFreq.find( s )->second == 1 ; } ) << '\n' ;
+   return 0 ;
+}