[pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

Author: pre-commit-ci[bot]

dynamic_programming/travelling_salesman_problem.py

@@ -48,8 +48,11 @@ def visit(city: int, mask: int) -> int:
                 min_cost = min(min_cost, new_cost)
         memo[city][mask] = int(min_cost)  # Store result as an integer
         return memo[city][mask]  # Return the cached result
+
     return visit(0, 1)  # Start from city 0 with city 0 visited
 
+
 if __name__ == "__main__":
     import doctest
+
     doctest.testmod()