Repo created

3party/succinct/elias_fano_list.hpp

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+#pragma once
+
+#include "elias_fano.hpp"
+
+namespace succinct {
+
+    struct elias_fano_list
+    {
+        typedef uint64_t value_type;
+
+        elias_fano_list() {}
+
+        template <typename Range>
+        elias_fano_list(Range const& ints)
+        {
+            typedef typename boost::range_const_iterator<Range>::type iterator_t;
+
+            size_t s = 0;
+            size_t n = 0;
+            for (iterator_t iter = boost::begin(ints);
+                 iter != boost::end(ints);
+                 ++iter) {
+                s += *iter;
+                n += 1;
+            }
+
+            elias_fano::elias_fano_builder ef_builder(s + 1, n);
+            size_t cur_base = 0;
+            for (iterator_t iter = boost::begin(ints);
+                 iter != boost::end(ints);
+                 ++iter) {
+                cur_base += *iter;
+                ef_builder.push_back(cur_base);
+            }
+            elias_fano(&ef_builder, false).swap(m_ef);
+        }
+
+        value_type operator[](size_t idx) const
+        {
+            return m_ef.delta(idx);
+        }
+
+        size_t size() const
+        {
+            return m_ef.num_ones();
+        }
+
+        size_t sum() const {
+            return m_ef.size() - 1;
+        }
+
+        void swap(elias_fano_list& other)
+        {
+            m_ef.swap(other.m_ef);
+        }
+
+        template <typename Visitor>
+        void map(Visitor& visit) {
+            visit
+                (m_ef, "m_ef")
+                ;
+        }
+
+    private:
+        elias_fano m_ef;
+    };
+
+}