5f5599009c
Rust version in src/main.rs (Cargo project) and a C++ port in cpp/main.cpp using raw pointers, both with VS Code build tasks and gdb-based debug configs. Vendors vscode-debug-visualizer and visualization as submodules for reference while building a custom node-table graph visualizer. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
101 lines
2.8 KiB
C++
101 lines
2.8 KiB
C++
#include <iostream>
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#include <optional>
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#include <sstream>
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// A single node containing data and a raw pointer to the next node
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template <typename T>
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struct Node {
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T data;
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Node<T>* next;
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};
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// The main wrapper for the linked list tracking the head node
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template <typename T>
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class LinkedList {
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public:
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LinkedList() : head_(nullptr) {}
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~LinkedList() {
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Node<T>* current = head_;
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while (current) {
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Node<T>* next = current->next;
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delete current;
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current = next;
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}
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}
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// Raw-pointer ownership can't be safely duplicated by a shallow copy
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LinkedList(const LinkedList&) = delete;
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LinkedList& operator=(const LinkedList&) = delete;
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// Add a new element to the front of the list
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void push_front(T data) {
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head_ = new Node<T>{std::move(data), head_};
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}
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// Remove and return the front element of the list
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std::optional<T> pop_front() {
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if (!head_) {
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return std::nullopt;
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}
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Node<T>* old_head = head_;
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T data = std::move(old_head->data);
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head_ = old_head->next;
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delete old_head;
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return data;
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}
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// Read the front element without removing it
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const T* peek_front() const {
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return head_ ? &head_->data : nullptr;
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}
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// Build a JSON string describing the list as a graph, for the VS Code
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// "Debug Visualizer" extension: watch `list.toDebugGraph()` while paused.
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// Schema: https://hediet.github.io/visualization/docs/visualization-data-schema.json
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std::string toDebugGraph() const {
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std::ostringstream json;
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json << "{\"kind\":{\"graph\":true},\"nodes\":[";
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for (Node<T>* n = head_; n; n = n->next) {
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if (n != head_) json << ",";
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json << "{\"id\":\"" << n << "\",\"label\":\"" << n->data << "\"}";
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}
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json << "],\"edges\":[";
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for (Node<T>* n = head_; n && n->next; n = n->next) {
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if (n != head_) json << ",";
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json << "{\"from\":\"" << n << "\",\"to\":\"" << n->next << "\"}";
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}
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json << "]}";
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return json.str();
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}
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private:
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Node<T>* head_;
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};
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// Force instantiation of every member, including toDebugGraph(), which
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// nothing in this file calls directly -- without this, gdb has no symbol
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// to invoke from the debugger's watch expression.
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template class LinkedList<int>;
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int main() {
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LinkedList<int> list;
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// Demonstrate pushing items
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list.push_front(10);
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list.push_front(20);
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list.push_front(30);
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// Demonstrate peeking at the top item
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if (const int* top = list.peek_front()) {
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std::cout << "Top element: " << *top << "\n"; // Output: 30
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}
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// Demonstrate popping items
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while (auto value = list.pop_front()) {
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std::cout << "Popped: " << *value << "\n";
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}
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return 0;
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}
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