feat: prepare the use of binary partitions for signatures

mo/src/problems/partition/moBinaryPartitionSwapNeighbor.h

@@ -0,0 +1,89 @@
+#pragma once
+
+#include <utility>
+
+#include <mo>
+
+#include "moBinaryPartition.h"
+
+template<class EOT, class Fitness=typename EOT::Fitness>
+class moBinaryPartitionSwapNeighbor :
+            public moBackableNeighbor<EOT,double>//,
+            // public moIndexNeighbor<EOT,double>
+{
+    public:
+        using AtomType = typename EOT::AtomType;
+        using ContainerType = typename EOT::ContainerType;
+        using moBackableNeighbor<EOT, Fitness>::fitness;
+        // using moIndexNeighbor<EOT, Fitness>::key;
+        // using moIndexNeighbor<EOT, Fitness>::index;
+
+        moBinaryPartitionSwapNeighbor( const size_t _selected_nb ) :
+            selected_nb(_selected_nb),
+            is_set(false)
+        {
+            assert(selected_nb > 0);
+        }
+
+        virtual void move(EOT& solution) override {
+            assert(is_set);
+            // Swap the two atoms.
+            solution.reject(this->reject);
+            solution.select(this->select);
+            assert(solution.selected.size() == this->selected_nb);
+
+            solution.invalidate();
+        }
+
+        virtual void moveBack(EOT& solution) override {
+            assert(is_set);
+            solution.reject(this->select);
+            solution.select(this->reject);
+            assert(solution.selected.size() == this->selected_nb);
+
+            solution.invalidate();
+        }
+
+        void set(AtomType in, AtomType out) {
+            this->select = in;
+            this->reject = out;
+            #ifndef NDEBUG
+                is_set = true;
+            #endif
+        }
+
+        std::pair<AtomType,AtomType> get() {
+            assert(is_set);
+            return std::make_pair(select, reject);
+        }
+
+        virtual bool equals(moBinaryPartitionSwapNeighbor<EOT,Fitness>& neighbor) {
+            auto [in, out] = neighbor.get();
+            return this->select == in and this->reject == out;
+        }
+
+        virtual std::string className() const override {
+            return "moBinaryPartitionSwapNeighbor";
+        }
+
+        virtual void printOn(std::ostream& out) const override {
+            assert(is_set);
+            out << selected_nb
+                << " -" << reject
+                << " +" << select;
+        }
+
+#ifndef NDEBUG
+    public:
+#else
+    protected:
+#endif
+        const size_t selected_nb;
+        AtomType select;
+        AtomType reject;
+        #ifndef NDEBUG
+            bool is_set;
+        #endif
+};
+
+