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formatting source-code for 153fb7b8a5

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2020-05-30 04:02:09 +00:00
parent 92fe9495ec
commit 8a2de9842b
175 changed files with 1671 additions and 3460 deletions
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61
greedy_algorithms/dijkstra.cpp
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@@ -4,27 +4,22 @@
using namespace std;
// Wrapper class for storing a graph
class Graph
{
class Graph {
public:
int vertexNum;
int **edges;
// Constructs a graph with V vertices and E edges
Graph(const int V)
{
Graph(const int V) {
// initializes the array edges.
this->edges = new int *[V];
for (int i = 0; i < V; i++)
{
for (int i = 0; i < V; i++) {
edges[i] = new int[V];
}
// fills the array with zeros.
for (int i = 0; i < V; i++)
{
for (int j = 0; j < V; j++)
{
for (int i = 0; i < V; i++) {
for (int j = 0; j < V; j++) {
edges[i][j] = 0;
}
}
@@ -33,19 +28,15 @@ class Graph
}
// Adds the given edge to the graph
void addEdge(int src, int dst, int weight)
{
void addEdge(int src, int dst, int weight) {
this->edges[src][dst] = weight;
}
};
// Utility function to find minimum distance vertex in mdist
int minDistance(int mdist[], bool vset[], int V)
{
int minDistance(int mdist[], bool vset[], int V) {
int minVal = INT_MAX, minInd = 0;
for (int i = 0; i < V; i++)
{
if (!vset[i] && (mdist[i] < minVal))
{
for (int i = 0; i < V; i++) {
if (!vset[i] && (mdist[i] < minVal)) {
minVal = mdist[i];
minInd = i;
}
@@ -55,11 +46,9 @@ int minDistance(int mdist[], bool vset[], int V)
}
// Utility function to print distances
void print(int dist[], int V)
{
void print(int dist[], int V) {
cout << "\nVertex Distance" << endl;
for (int i = 0; i < V; i++)
{
for (int i = 0; i < V; i++) {
if (dist[i] < INT_MAX)
cout << i << "\t" << dist[i] << endl;
else
@@ -70,16 +59,14 @@ void print(int dist[], int V)
// The main function that finds the shortest path from given source
// to all other vertices using Dijkstra's Algorithm.It doesn't work on negative
// weights
void Dijkstra(Graph graph, int src)
{
void Dijkstra(Graph graph, int src) {
int V = graph.vertexNum;
int mdist[V]; // Stores updated distances to vertex
bool vset[V]; // vset[i] is true if the vertex i included
// in the shortest path tree
// Initialise mdist and vset. Set distance of source as zero
for (int i = 0; i < V; i++)
{
for (int i = 0; i < V; i++) {
mdist[i] = INT_MAX;
vset[i] = false;
}
@@ -87,17 +74,14 @@ void Dijkstra(Graph graph, int src)
mdist[src] = 0;
// iterate to find shortest path
for (int count = 0; count < V - 1; count++)
{
for (int count = 0; count < V - 1; count++) {
int u = minDistance(mdist, vset, V);
vset[u] = true;
for (int v = 0; v < V; v++)
{
for (int v = 0; v < V; v++) {
if (!vset[v] && graph.edges[u][v] &&
mdist[u] + graph.edges[u][v] < mdist[v])
{
mdist[u] + graph.edges[u][v] < mdist[v]) {
mdist[v] = mdist[u] + graph.edges[u][v];
}
}
@@ -107,8 +91,7 @@ void Dijkstra(Graph graph, int src)
}
// Driver Function
int main()
{
int main() {
int V, E, gsrc;
int src, dst, weight;
cout << "Enter number of vertices: ";
@@ -116,8 +99,7 @@ int main()
cout << "Enter number of edges: ";
cin >> E;
Graph G(V);
for (int i = 0; i < E; i++)
{
for (int i = 0; i < E; i++) {
cout << "\nEdge " << i + 1 << "\nEnter source: ";
cin >> src;
cout << "Enter destination: ";
@@ -126,12 +108,9 @@ int main()
cin >> weight;
// makes sure source and destionation are in the proper bounds.
if (src >= 0 && src < V && dst >= 0 && dst < V)
{
if (src >= 0 && src < V && dst >= 0 && dst < V) {
G.addEdge(src, dst, weight);
}
else
{
} else {
cout << "source and/or destination out of bounds" << endl;
i--;
continue;