feat: operator overloading for append

src/core/ranges/internal/ranges.cc

@@ -5,20 +5,30 @@ using klotski::cases::Ranges;
 using klotski::codec::CommonCode;
 using klotski::cases::RangesUnion;
 
+static constexpr auto heads = std::to_array<uint64_t>({
+    0x0, 0x1, 0x2, 0x4, 0x5, 0x6,
+    0x8, 0x9, 0xA, 0xC, 0xD, 0xE,
+});
+
 void Ranges::reverse() {
     for (auto &x : *this) {
         x = range_reverse(x);
     }
 }
 
-std::vector<CommonCode> RangesUnion::codes() const {
-    constexpr auto heads = std::to_array<uint64_t>({
-        0x0, 0x1, 0x2,
-        0x4, 0x5, 0x6,
-        0x8, 0x9, 0xA,
-        0xC, 0xD, 0xE,
-    });
+Ranges& Ranges::operator+=(const Ranges &ranges) {
+    this->insert(this->end(), ranges.begin(), ranges.end());
+    return *this;
+}
 
+RangesUnion& RangesUnion::operator+=(const RangesUnion &ranges_union) {
+    for (const auto head : heads) {
+        (*this)[head] += ranges_union[head];
+    }
+    return *this;
+}
+
+std::vector<CommonCode> RangesUnion::codes() const {
     size_type size = 0;
     for (const auto head : heads) {
         size += (*this)[head].size();

src/core/ranges/ranges.h

@@ -14,6 +14,9 @@ namespace klotski::cases {
 
 class Ranges final : public std::vector<uint32_t> {
 public:
+    /// Append the ranges from another instance.
+    Ranges& operator+=(const Ranges &ranges);
+
     /// Spawn klotski-ranges that match the specified block numbers.
     void spawn(int n, int n_2x1, int n_1x1);
 
@@ -29,7 +32,10 @@ public:
 
 class RangesUnion final : public std::array<Ranges, 16> {
 public:
-    /// Export RangesUnion as CommonCode list.
+    /// Append the ranges from another instance.
+    RangesUnion& operator+=(const RangesUnion &ranges_union);
+
+    /// Export the RangesUnion as CommonCode list.
     [[nodiscard]] std::vector<codec::CommonCode> codes() const;
 };