New cpp folder structure

Signed-off-by: Alexander Borsuk <me@alex.bio>

libs/indexer/cell_value_pair.hpp

@@ -0,0 +1,43 @@
+#pragma once
+
+#include "base/macros.hpp"
+
+#include <cstdint>
+
+namespace covering
+{
+template <typename Value>
+class CellValuePair
+{
+public:
+  using ValueType = Value;
+
+  CellValuePair() = default;
+
+  CellValuePair(uint64_t cell, Value value)
+    : m_cellLo(UINT64_LO(cell)), m_cellHi(UINT64_HI(cell)), m_value(value)
+  {
+  }
+
+  bool operator<(CellValuePair const & rhs) const
+  {
+    if (m_cellHi != rhs.m_cellHi)
+      return m_cellHi < rhs.m_cellHi;
+    if (m_cellLo != rhs.m_cellLo)
+      return m_cellLo < rhs.m_cellLo;
+    return m_value < rhs.m_value;
+  }
+
+  uint64_t GetCell() const { return UINT64_FROM_UINT32(m_cellHi, m_cellLo); }
+  Value GetValue() const { return m_value; }
+
+private:
+  uint32_t m_cellLo = 0;
+  uint32_t m_cellHi = 0;
+  Value m_value = 0;
+};
+
+// For backward compatibility.
+static_assert(sizeof(CellValuePair<uint32_t>) == 12);
+static_assert(std::is_trivially_copyable<CellValuePair<uint32_t>>::value);
+}  // namespace covering