diff --git a/run.py b/run.py
index 4d62172..0fe88ac 100644
--- a/run.py
+++ b/run.py
@@ -51,7 +51,9 @@ def run(show_plots=False, verbose=False):
                     solver.pop()
 
         if prob_instance.exist_opt and show_plots:
-            solver.algorithm_name="optimal"
+            solver = SolverTSP("optimal", prob_instance)
+            # solver.name_method = "optimal"  # TODO ask umberto details
+
             solver.solution = np.concatenate([prob_instance.optimal_tour, [prob_instance.optimal_tour[0]]])
             solver.plot_solution()
 
diff --git a/src/TSP_solver.py b/src/TSP_solver.py
index 2562102..70261fa 100644
--- a/src/TSP_solver.py
+++ b/src/TSP_solver.py
@@ -24,7 +24,7 @@ class SolverTSP:
     found_length: float
 
     def __init__(self, algorithm_name, problem_instance):
-        assert algorithm_name in available_solvers, f"the {algorithm_name} initializer is not available currently."
+        # assert algorithm_name in available_solvers, f"the {algorithm_name} initializer is not available currently."
         self.duration = np.inf
         self.algorithm_name = algorithm_name
         self.algorithms = [algorithm_name]
diff --git a/src/io_tsp.py b/src/io_tsp.py
index 551380f..c2676a1 100644
--- a/src/io_tsp.py
+++ b/src/io_tsp.py
@@ -16,7 +16,7 @@ class ProblemInstance:
 
     def __init__(self, name_tsp):
         self.read_instance(name_tsp)
-        self.exist_opt = None  # TODO determine default value
+        self.exist_opt = False  # TODO determine default value
         self.optimal_tour = None
 
     def read_instance(self, name_tsp):
@@ -40,8 +40,7 @@ class ProblemInstance:
             self.points[i, 2] = line_i[2]
 
         self.create_dist_matrix()
-        self.exist_opt = False
-        if [name for name in ["eil76", "kroA100"] if name in name_tsp]:
+        if name_tsp in ["./problems/eil76.tsp", "./problems/kroA100.tsp"]:
             self.exist_opt = True
             file_object = open(name_tsp.replace(".tsp", ".opt.tour"))
             data = file_object.read()