# 2. Apply the method `run`, that will search and return a solution.
# 3. Retrieve information from the solution.
#
-# ~~~~
+# ~~~~nitish
# var p: BacktrackProblem = new MyProblem
# var solver = p.solve
# var res = solver.run
problem.backtrack(state, a)
node = node.parent
+ assert node != null
continue
end