Add files via upload

23.DijkstraAlgorithm.cpp

@@ -0,0 +1,67 @@
+/*
+ * This program constructs a graph from user inputs and
+ * finds shortest path distances to everynode from node 0 using
+ * Dijkstra's Shortest Path algorithm
+ *
+ *      Coded by: Abdurrezak Efe
+ * */
+
+#include <iostream>
+using namespace std;
+
+const int V = 1000; //assumed number of vertices
+int edges[V+1][V+1] = {0}; //the graph itself
+
+int minDistanceIndex(int distance[], bool inPath[], int v)
+{
+    int minDist = 999999999, minIndex=-1;
+
+    for(int i=0; i<v; i++)
+        if(!inPath[i] && distance[i] < minDist)
+            minDist = distance[i], minIndex = i;
+
+    return minIndex;
+}
+
+void Dijkstra( int v, int e)
+{
+    int distance[v];
+    bool inPath[v];
+
+    for(int i=0;i<v;i++)
+        distance[i] = 999999999, inPath[i] = false;
+
+    distance[0] = 0;
+
+    int vertices = 0;
+    while(vertices < v-1)
+    {
+        int u = minDistanceIndex(distance, inPath, v);
+
+        inPath[u] = true;
+
+        //operating on u's neighbors to add the smallest
+        for(int i=0; i<v; i++)
+            if( !inPath[i] && edges[u][i] && distance[u]+edges[u][i] < distance[i])
+                distance[i] = distance[u]+edges[u][i];
+
+        vertices++;
+    }
+
+    int i = 0;
+    while(i<v)
+        cout << "vertex: " <<i << ", distance: " <<  distance[i]  << endl, i++;
+}
+
+int main()
+{
+    int v,e;
+    cin >> v >> e;
+
+    //constructing the graph
+    int x,y,w;
+    for(int i=0;i<e;i++)
+        cin >> x >> y >> w, edges[x][y] = edges[y][x] = w;
+
+    Dijkstra(v, e);
+}