less.h + greater.h -> bug in greater

Author: stephanlindauer

cpp4j/cpp4j.pro

@@ -14,5 +14,7 @@ SOURCES += rationalnumber.cpp \
 HEADERS += \
     rationalnumber.h \
     rationalnumberarray.h \
-    pair.h
+    pair.h \
+    less.h \
+    greater.h
 

cpp4j/greater.h

@@ -0,0 +1,22 @@
+#ifndef GREATER_H
+#define GREATER_H
+
+#include "less.h"
+
+template <class T> class Greater {
+
+public :
+
+    bool operator ()(const T &left, const T &right){
+        Less<T> less;
+        // nicht kleiner && nicht gleich
+        bool lesser = less(left, right);
+        bool equal = !less(left, right) && !less(right,left);
+
+        return !lesser && !equal;
+    }
+
+};
+
+
+#endif // GREATER_H

cpp4j/less.h

@@ -0,0 +1,16 @@
+#ifndef LESS_H
+#define LESS_H
+
+
+template <class T> class Less {
+
+public :
+
+    bool operator ()(const T &left, const T &right){
+        return left < right;
+    }
+
+};
+
+
+#endif // LESS_H

cpp4j/testTemplates.cpp

@@ -14,6 +14,8 @@ using namespace std;
 
 // include your own header files here...
 #include "pair.h"
+#include "less.h"
+#include "greater.h"
 //#include "order.h"
 //#include "tree.h"
 //#include "map.h"
@@ -79,6 +81,12 @@ int testTemplates(void)
     cout << "2<3 == " << lessInt(2,3) << endl;
     cout << "4<3 == " << lessInt(4,3) << endl;
 
+    Greater<int> greaterInt;
+    assert ( greaterInt(4,3) == 1 );
+    assert ( greaterInt(3,4) == 0 );
+    assert ( greaterInt(3,3) == 0 );
+
+
 #if 0 // move this line down while your implementation proceeds...
     /////////////////////////////////////////
     // TEST PAIR ORDER