Problem: Tracing UCS Search for the Romanian Railroad problem.

Find the shortest path from Arad to Bucharest, using Algorithm UCS. Show the OPEN list at each cycle of the algorithm. You can refer to each city by the first letter of its name. A concise way of showing your answer would be to show the name of each node as it is added to OPEN followed by its depth $($cost to reach that node from the start$)$