This commit is contained in:
Christopher Sanden
2025-11-17 17:02:46 +01:00
parent 730987913e
commit 1e00ba3521
6 changed files with 342 additions and 9 deletions

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@@ -3,10 +3,11 @@ set(CMAKE_CXX_STANDARD_REQUIRED ON)
# "ON" = build Option 1, "OFF" = build Option 2.
option(BUILD_ASSIGNMENT_04_OPTION_1 "Build Assignment Option 1 (Standard)" OFF)
option(BUILD_ASSIGNMENT_04_OPTION_1 "Build Assignment Option 1 (Standard)" ON)
add_executable(Assignment-04
main.cpp
option1.cpp
)
if(BUILD_ASSIGNMENT_04_OPTION_1)

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@@ -28,16 +28,18 @@ To force an update (e.g., in Visual Studio):
#include <iostream>
#include <string_view>
#include "option1.h"
static constexpr std::string_view AssignmentName = "Category 4: Graphs & Dijkstra's Algorithm";
#if ASSIGNMENT_04_OPTION == 1
static constexpr std::string_view AssignmentOption = "Option 1 (Standard): Data Center Network Monitor.";
/*
#if ASSIGNMENT_04_OPTION == 1
#include "option1.h"
#elif ASSIGNMENT_04_OPTION == 2
static constexpr std::string_view AssignmentOption = "Option 2 (Advanced): Inter-city Logistics Router.";
#include "option2.h"
#endif
*/
int main(int argc, char* argv[])
{

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@@ -1,6 +1,261 @@
#include "option1.h"
#include <iostream>
#include "SharedLib.h"
// Necessary declarations
constexpr float INF = 1e9f;
Graph g;
std::unordered_map<std::string, int> nameToIndex;
std::string filename = R"(C:\Users\csand\IKT203\Exam\IKT203Exam\DATA\network_graph.txt)"; // Local path to MY graph file
//////////////////////////////// Callbacks ////////////////////////////////
bool onNodeRead(const int aIndex, const int aTotalCount, const std::string& aNode)
{
const int idx = g.AddVertex(aNode);
nameToIndex[aNode] = idx;
return true;
}
bool onEdgeRead(const int aIndex, const int aTotalCount, const std::string& aFromNode, const std::string& aToNode, const float aWeight)
{
const int fromIdx = nameToIndex[aFromNode];
const int toIdx = nameToIndex[aToNode];
g.AddUndirectedEdge(fromIdx, toIdx, aWeight);
return true;
}
//////////////////////////////// Dijkstra algorithm ////////////////////////////////
float Dijkstra(const Graph& graph, int src, int dst, std::vector<int>& outPath)
{
const int n = graph.GetVertexCount();
std::vector<float> dist(n, INF);
std::vector<int> prev(n, -1);
std::vector<bool> visited(n, false);
dist[src] = 0.0f;
MinHeap heap;
heap.Push(src, 0.0f);
while (!heap.isEmpty()) {
HeapNode* node = heap.Pop();
const int u = node->vertex;
float d = node->distance;
delete node;
if (visited[u])
continue;
visited[u] = true;
if (u == dst)
break;
for (const TEdge* e : graph.GetEdges(u)) {
int v = e->toIndex;
float w = e->weight;
if (visited[v])
continue;
if (dist[u] + w < dist[v]) {
dist[v] = dist[u] + w;
prev[v] = u;
heap.Push(v, dist[v]);
}
}
}
outPath.clear();
if (dist[dst] == INF)
return INF;
for (int v = dst; v != -1; v = prev[v])
outPath.push_back(v);
std::reverse(outPath.begin(), outPath.end());
return dist[dst];
}
//////////////////////////////// Class logic ////////////////////////////////
// Graph
Graph::~Graph()
{
for (TVertex* v : vertices) {
for (TEdge* e : v->edges) {
delete e;
}
delete v;
}
}
int Graph::AddVertex(const std::string& name)
{
auto* v = new TVertex;
v->name = name;
vertices.push_back(v);
return static_cast<int>(vertices.size()) - 1;
}
void Graph::AddUndirectedEdge(int fromIndex, int toIndex, float weight)
{
TEdge* e1 = new TEdge;
e1->toIndex = toIndex;
e1->weight = weight;
TEdge* e2 = new TEdge;
e2->toIndex = fromIndex;
e2->weight = weight;
vertices[fromIndex]->edges.push_back(e1);
vertices[toIndex]->edges.push_back(e2);
}
int Graph::GetVertexCount() const
{
return static_cast<int>(vertices.size());
}
const TVertex *Graph::GetVertex(int index) const
{
return vertices[index];
}
const std::vector<TEdge*>& Graph::GetEdges(const int index) const
{
return vertices[index]->edges;
}
// Heap
MinHeap::~MinHeap()
{
for (HeapNode* n : data)
delete n;
}
bool MinHeap::isEmpty() const
{
return data.empty();
}
void MinHeap::Push(int vertex, float dist)
{
auto* n = new HeapNode{vertex, dist};
data.push_back(n);
HeapUp(static_cast<int>(data.size()) - 1);
}
HeapNode* MinHeap::Pop()
{
if (data.empty())
return nullptr;
HeapNode* root = data[0];
data[0] = data.back();
data.pop_back();
if (!data.empty())
HeapDown(0);
return root;
}
void MinHeap::HeapUp(int idx)
{
while (idx > 0) {
int parent = (idx - 1) / 2;
if (data[parent]->distance <= data[idx]->distance)
break;
std::swap(data[idx], data[parent]);
idx = parent;
}
}
void MinHeap::HeapDown(int idx)
{
int n = static_cast<int>(data.size());
while (true) {
int left = 2 * idx + 1;
int right = 2 * idx + 2;
int smallest = idx;
if (left < n && data[left]->distance < data[smallest]->distance)
smallest = left;
if (right < n && data[right]->distance < data[smallest]->distance)
smallest = right;
if (smallest == idx)
break;
std::swap(data[idx], data[smallest]);
idx = smallest;
}
}
int RunApp() {
readGraphFromFile(filename, onNodeRead, onEdgeRead);
// Debug: Print all nodes and vertices
/*
pack("Graph");
for (int i = 0; i < g.GetVertexCount(); i++) {
const TVertex* v = g.GetVertex(i);
std::cout << i << ": " << v->name << std::endl;
for (const TEdge* e : g.GetEdges(i)) {
std::cout << " -> " << e->toIndex << " (weight = " << e->weight << ")" << std::endl;
}
}
*/
/* Debug heap test
pack("Heap");
MinHeap test;
test.Push(1, 5.0f);
test.Push(2, 3.0f);
test.Push(3, 10.0f);
while (!test.isEmpty())
{
const HeapNode* n = test.Pop();
std::cout << "(" << n->vertex << ", " << n->distance << ")" << "\n";
delete n;
}
printline();
*/
std::cout << "\nGraph:" << std::endl;
for (int i = 0; i < g.GetVertexCount(); ++i)
std::cout << i << ": " << g.GetVertex(i)->name << std::endl;
int src, dst;
std::cout << "\nEnter source index: ";
std::cin >> src;
std::cout << "\nEnter destination index: ";
std::cin >> dst;
if (src < 0 || src >= g.GetVertexCount() ||
dst < 0 || dst >= g.GetVertexCount()) {
std::cout << "Invalid indices.\n";
return 0;
}
std::vector<int> path;
float total = Dijkstra(g, src, dst, path);
if (total >= INF) {
std::cout << "\nNo path between those nodes.\n";
} else {
std::cout << "\nLowest latency path: ";
for (size_t i = 0; i < path.size(); ++i) {
std::cout << g.GetVertex(path[i])->name;
if (i + 1 < path.size()) std::cout << " -> ";
}
std::cout << " \n(Total: " << total << " ms)\n";
}
printline();
return 0;
}
}

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@@ -2,6 +2,81 @@
#ifndef OPTION1_H
#define OPTION1_H
#include <iostream>
#include <string>
#include <unordered_map>
#include <vector>
// Structs and classes
struct TEdge {
int toIndex;
float weight;
};
struct TVertex {
std::string name;
std::vector<TEdge*> edges;
};
struct HeapNode {
int vertex;
float distance;
};
class MinHeap {
private:
std::vector<HeapNode*> data;
void HeapUp(int idx);
void HeapDown(int idx);
public:
~MinHeap();
[[nodiscard]] bool isEmpty() const;
void Push(int vertex, float dist);
HeapNode* Pop();
};
class Graph {
private:
std::vector<TVertex*> vertices; // Owns all TVertex*
public:
~Graph();
int AddVertex(const std::string& name);
void AddUndirectedEdge(int fromIndex, int toIndex, float weight);
[[nodiscard]] int GetVertexCount() const;
[[nodiscard]] const TVertex* GetVertex(int index) const;
[[nodiscard]] const std::vector<TEdge*>& GetEdges(int index) const;
};
// Callbacks & funcs
bool onNodeRead(int aIndex, int aTotalCount, const std::string& aNode);
bool onEdgeRead(int aIndex, int aTotalCount, std::string& aFromNode, std::string& aToNode, float aWeight);
float Dijkstra(const Graph& graph, int src, int dst, std::vector<int>& outPath);
// Terminal tidying
inline void printline()
{
std::cout << "----------------------------------------" << std::endl;
}
inline void pack(const std::string& line)
{
std::cout << "\n\n\n" << std::endl;
printline();
std::cout << line << std::endl;
printline();
}
int RunApp();

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@@ -27,7 +27,7 @@ static bool EdgeReadCallback(const int aIndex, const int aTotalCount, const std:
return true;
}
/*
int RunApp()
{
@@ -44,4 +44,4 @@ int RunApp()
std::cout << "\nFinished reading graph." << std::endl;
return 0;
}
}*/

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@@ -2,8 +2,8 @@
#ifndef OPTION2_H
#define OPTION2_H
/*
int RunApp();
*/
#endif // OPTION2_H