1 files changed, 73 insertions, 0 deletions
diff --git a/challenge-197/ulrich-rieke/cpp/ch-2.cpp b/challenge-197/ulrich-rieke/cpp/ch-2.cpp
new file mode 100644
index 0000000000..e9a0dd71da
--- /dev/null
+++ b/challenge-197/ulrich-rieke/cpp/ch-2.cpp
@@ -0,0 +1,73 @@
+#include <iostream>
+#include <vector>
+#include <string>
+#include <algorithm>
+#include <utility>
+#include <map>
+
+bool myCondition( const std::vector<int> & numbers ) {
+  int len = numbers.size( ) ;
+  if ( len == 3 ) {
+      return ( (numbers[0] < numbers[1]) && ( numbers[1] > numbers[2] ) ) ;
+  }
+  if ( len > 3 ) {
+      for ( int i = 0 ; i < len - 1  ; i++ ) {
+    if ( i % 2 == 0 ) {
+        if ( ! (numbers[ i ] < numbers[ i + 1 ]) ) {
+          return false ;
+        }
+    }
+    else {
+        if ( ! (numbers[ i ] > numbers[ i + 1 ] ) ) {
+          return false ;
+        }
+    }
+      }
+  }
+  return true ;
+}
+
+void printOut( const std::vector<int> & nums ) {
+  std::cout << '(' ;
+  for ( int i : nums ) {
+      std::cout << i << ' ' ;
+  }
+  std::cout << ')' << std::endl ;
+}
+
+int main( ) {
+  std::cout << "Please enter at least 3 integers, 0 to end!\n" ;
+  std::vector<int> numbers ;
+  int num ;
+  std::cin >> num ;
+  while ( num != 0  ) {
+      numbers.push_back( num ) ;
+      std::cin >> num ;
+  }
+  while ( numbers.size( ) < 3 ) {
+      std::cout << "You should enter at least 3 numbers!\n!" ;
+      std::cin >> num ;
+      numbers.push_back( num ) ;
+  }
+  std::map<int , int> frequencies ;
+  for ( int i : numbers ) {
+      frequencies[i]++;
+  }
+  std::vector<std::pair<int , int>> thePairs ( frequencies.begin( ) ,
+    frequencies.end( ) ) ;
+  std::pair<int , int> maxPair = *std::max_element( thePairs.begin( ) ,
+    thePairs.end( ) , []( const auto & p1 , const auto & p2 ) {
+    return p1.second > p2.second ; } ) ;
+  if ( maxPair.second >= numbers.size( ) - 1 ) {
+      std::cout << "No wiggling possible!\n" ;
+  }
+  else {
+      sort( numbers.begin( ) , numbers.end( ) ) ;
+      while ( std::next_permutation( numbers.begin( ) , numbers.end( ))) {
+    if ( myCondition( numbers ) ) {
+        printOut( numbers ) ;
+    }
+      }
+  }
+  return 0 ;
+}