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Please implement the A* search algorithm in Python for the problem scenario below. Please explain your code and your approach.
PROBLEM SCENARIO
On holiday, a flight currently wants to travel to Bucharest from Arad. But there is
no direct way to Bucharest from Arad. However, the cities are connected with
each other like a graph. The distance between the connected cities are given. The
flight wants to travel through the most optimal way. To find the optimal path to
travel, another information is provided: the straight line distance between any city
and the final destination (Bucharest).
Now apply A* search to determine the most optimal value for the route Arad to
Bucharest and help the flight. You have to use the straight line distance as the
heuristic value for the cities.
City Heuristic value City Heuristic value
Arad 366 Mehadia 241
Bucharest 0 Neamt 234
Craiova 160 Oradea 380
Eforie 161 Pitesti 100
Fagaras 176 Rimnicu Vilcea 193
Dobreta 242 Timisoara 329
Hirsova 151 Urziceni 80
lasi 226 Vaslui 199
Lugoj 244 Zerind 374
For simplicity, assume these notations
Arad A Neamt F
Bucharest Z Oradea B
Craiova S Pitesti P
Eforie T Rimnicu Vilcea R
Fagaras O Timisoara C
Dobreta V Urziceni D
Hirsova N Vaslui H
lasi Q Zerind E
Lugoj G
Mehadia L
INPUTS
Your txt file should take each node followed by each destination it can reach and
their corresponding distance and heuristics. You are to read the file then ask the
user to input the starting and the destination point.
OUTPUTS
The output will contain the total distance from the starting point to the
destination followed by printing the nodes it followed to calculate the distance.
SAMPLE INPUT
In the text file:
Arad 366 Zerind 75 Sibiu 140 Timisoara 118
Zerind 374 Arad 75 Oradea 71
Oradea 380 Zerind 71 Sibiu 151
... ... ... ... ... ...
Bucharest 0 Pitesti 101 Fagaras 211 Giurgiu 90 Urziceni 85
Giurgiu 77 Bucharest 90
... ... ... ... ... …
The text file is arranged as follows:
Each line starts with a node followed by the heuristic of that node
Then the neighboring nodes and the distance from the parent node is given as a pair
All neighboring city-distance pairs are listed after the heuristic.
For example, the text file starts with Arad which has a heuristic of 366. It is the parent
node to Zerind, Sibiu and Timisoara which are 75, 140 and 118 km away from Arad.
Notice that since Bucharest is the End node which is why it has a heuristic of 0.
In console:
Start node: Arad
Destination: Bucharest
Sample output:
Path: Arad -> Sibiu -> Rimnicu -> Pitesti -> Bucharest
Total distance: 418 km
If there is no path found from the Start node to the End node, simply print “NO
PATH FOUND
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