Added backtracking to the city_dikstra

city_dijkstra.py

@@ -11,14 +11,17 @@ def mans_cels(city_1, city_2, matrix, cities):
     visited = [False] * len(cities)
 
     for iteration in range(0, len(cities)):
-        # for iteration in range(0, len(sum_dist)):
         for node_to_visit in range(0, len(sum_dist)):
             length = matrix[curr_node][node_to_visit]
             node_visited = visited[node_to_visit]
-            visiting_curr = node_to_visit == curr_node
+            visiting_curr = node_to_visit == curr_node or length >= 100
             cannot_reach = length == inf
+
+            # Determine wether we're trying to access an invalid city
             if visiting_curr or cannot_reach or node_visited:
                 continue
+
+            # Calculate the new length to each of the connected city
             if sum_dist[curr_node] + length < sum_dist[node_to_visit]:
                 sum_dist[node_to_visit] = sum_dist[curr_node] + length
 
@@ -26,23 +29,38 @@ def mans_cels(city_1, city_2, matrix, cities):
         curr_smallest_len = inf
         curr_smallest_id = 0
 
-        for iter_node in range(0, len(cities)):
-            if not visited[iter_node
-                          ] and sum_dist[iter_node] < curr_smallest_len:
-                curr_smallest_len = sum_dist[iter_node]
-                curr_smallest_id = iter_node
+        # Find a connected node with the least distance
+        for i_node in range(0, len(cities)):
+            if not visited[i_node] and sum_dist[i_node] < curr_smallest_len:
+                curr_smallest_len = sum_dist[i_node]
+                curr_smallest_id = i_node
+
+        # If we're at the end node, trace back the graph
+        if visited[end_node]:
+            route = [cities[end_node]]
+            pos = end_node
+
+            while (pos != start_node):
+                for i_node in range(0, len(sum_dist)):
+                    if i_node != pos and matrix[i_node][pos] != inf and sum_dist[pos] - \
+                            matrix[i_node][pos] == sum_dist[i_node]:
+                        route.append(cities[i_node])
+                        pos = i_node
+                        break
+
+            route.reverse()
+            print(route)
+
+            break
         city_to_visit = cities[curr_smallest_id]
         print(f"Next city to visit {city_to_visit}")
         curr_node = curr_smallest_id
-        if visited[end_node]:
-            break
-
-    print("sum_dist", sum_dist)
-    print("visited", visited)
 
 
 if __name__ == "__main__":
-    matrix_data = generate_matrix(50)
+    matrix_data = generate_matrix()
     cities_string = ", ".join(matrix_data['cities'])
     print(f"Availaible cities {cities_string}")
-    mans_cels("Balvi", "Aluksne", matrix_data["matrix"], matrix_data["cities"])
\ No newline at end of file
+    mans_cels(
+        "Ventspils", "Riga", matrix_data["matrix"], matrix_data["cities"]
+    )