From 7d8d5e1bff44594a323acfb02f0c34df6242a2fe Mon Sep 17 00:00:00 2001
From: jermp <jeis90@gmail.com>
Date: Wed, 25 May 2022 16:59:05 +0200
Subject: [PATCH] count num distinct minimizers during merge

---
 include/builder/build.cpp | 12 +-----------
 include/builder/util.hpp  |  9 +++++++++
 2 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/include/builder/build.cpp b/include/builder/build.cpp
index f8e6862..999a4d8 100644
--- a/include/builder/build.cpp
+++ b/include/builder/build.cpp
@@ -30,9 +30,6 @@ void dictionary::build(std::string const& filename, build_configuration const& b
         throw std::runtime_error("l must be <= " + std::to_string(constants::max_l));
     }
 
-    // TODO: have user input here
-    std::string tmp_dirname = constants::default_tmp_dirname;
-
     m_k = build_config.k;
     m_m = build_config.m;
     m_seed = build_config.seed;
@@ -77,15 +74,8 @@ void dictionary::build(std::string const& filename, build_configuration const& b
     {
         mm::file_source<minimizer_tuple> input(data.minimizers.get_minimizers_filename(),
                                                mm::advice::sequential);
-
-        uint64_t num_minimizers = 0;
-        for (minimizers_tuples_iterator it(input.data(), input.data() + input.size());
-             it.has_next(); it.next()) {
-            ++num_minimizers;
-        }
-
         minimizers_tuples_iterator iterator(input.data(), input.data() + input.size());
-        m_minimizers.build(iterator, num_minimizers);
+        m_minimizers.build(iterator, data.minimizers.num_minimizers());
         input.close();
     }
     timer.stop();
diff --git a/include/builder/util.hpp b/include/builder/util.hpp
index 73a49ef..dfc3e16 100644
--- a/include/builder/util.hpp
+++ b/include/builder/util.hpp
@@ -163,6 +163,7 @@ struct minimizers_tuples {
     minimizers_tuples(std::string tmp_dirname = constants::default_tmp_dirname)
         : m_buffer_size(0)
         , m_num_files_to_merge(0)
+        , m_num_minimizers(0)
         , m_run_identifier(pthash::clock_type::now().time_since_epoch().count())
         , m_tmp_dirname(tmp_dirname) {
         m_buffer_size = ram_limit / sizeof(minimizer_tuple);
@@ -263,9 +264,14 @@ struct minimizers_tuples {
         if (!out.is_open()) throw std::runtime_error("cannot open file");
 
         uint64_t num_written_tuples = 0;
+        uint64_t prev_minimizer = constants::invalid;
         while (!idx_heap.empty()) {
             minimizer_tuple const* begin = iterators[idx_heap.front()].begin;
             out.write(reinterpret_cast<char const*>(begin), sizeof(minimizer_tuple));
+            if ((*begin).minimizer != prev_minimizer) {
+                prev_minimizer = (*begin).minimizer;
+                ++m_num_minimizers;
+            }
             num_written_tuples += 1;
             if (num_written_tuples % 50000000 == 0) {
                 std::cout << "num_written_tuples = " << num_written_tuples << std::endl;
@@ -286,11 +292,14 @@ struct minimizers_tuples {
         m_num_files_to_merge = 0;  // any other call to merge() will do nothing
     }
 
+    uint64_t num_minimizers() const { return m_num_minimizers; }
+
     void remove_tmp_file() { std::remove(get_minimizers_filename().c_str()); }
 
 private:
     uint64_t m_buffer_size;
     uint64_t m_num_files_to_merge;
+    uint64_t m_num_minimizers;
     uint64_t m_run_identifier;
     std::string m_tmp_dirname;
     std::vector<minimizer_tuple> m_buffer;