2023: avoid unnecessary copies when returning std::pair

yut23 · Feb 21, 2024 · 98d6aa2 · 98d6aa2
1 parent f74bba7
commit 98d6aa2
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Showing 4 changed files with 6 additions and 6 deletions.
diff --git a/2023/src/day18.hpp b/2023/src/day18.hpp
@@ -45,7 +45,7 @@ read_instructions(std::istream &is) {
             instructions2.push_back(std::move(color_instr));
         }
     }
-    return {instructions1, instructions2};
+    return {std::move(instructions1), std::move(instructions2)};
 }
 
 } // namespace aoc::day18

diff --git a/2023/src/day19.hpp b/2023/src/day19.hpp
@@ -212,7 +212,7 @@ std::pair<PartCategorizer, std::vector<Part>> read_input(std::istream &is) {
     while (read_part(is, part)) {
         parts.push_back(std::move(part));
     }
-    return {cat, parts};
+    return {std::move(cat), std::move(parts)};
 }
 
 class Part2Solver {

diff --git a/2023/src/day24.hpp b/2023/src/day24.hpp
@@ -81,7 +81,7 @@ find_intersection_xy(const Hailstone &a, const Hailstone &b) {
 }
 
 template <class T>
-std::tuple<aoc::ds::Grid<T>, std::vector<T>>
+std::pair<aoc::ds::Grid<T>, std::vector<T>>
 make_system(const std::vector<aoc::day24::Hailstone> &stones,
             const std::pair<std::size_t, std::size_t> &pair_1,
             const std::pair<std::size_t, std::size_t> &pair_2) {
@@ -133,7 +133,7 @@ make_system(const std::vector<aoc::day24::Hailstone> &stones,
         }
         ++i;
     }
-    return {A, b};
+    return {std::move(A), std::move(b)};
 }
 
 std::vector<Hailstone> read_stones(std::istream &is) {

diff --git a/2023/src/graph_traversal.hpp b/2023/src/graph_traversal.hpp
@@ -373,7 +373,7 @@ longest_path_dag(const Key &source, GetNeighbors &&get_neighbors,
         path.emplace_back(it->second.second);
     }
     std::ranges::reverse(path);
-    return {max_distance, path};
+    return {max_distance, std::move(path)};
 }
 
 /**
@@ -511,7 +511,7 @@ a_star(const Key &source, GetNeighbors &&get_neighbors,
                 path.emplace_back(it->second.key);
             }
             std::ranges::reverse(path);
-            return {curr.dist, path};
+            return {curr.dist, std::move(path)};
         }
         for (const Key &neighbor : get_neighbors(curr.key)) {
             if constexpr (use_visited) {