Consider the following Branch-and-bound tree (incomplete) for a minimization problem, where each node is assigned a node number starting from 0. For each sub-problem, the objective function value of the LP-relaxation is provided, indicated by the number inside the node. Furthermore, sub-problems for which integral solutions are obtained are highlighted in grey, and the nodes of infeasible sub-problems are colored black.
Create a table with the following columns: Node number, Lower Bound, Upper Bound, Gap. The table should list the order in which the sub-problems are solved when considering the depth-first node selection rule. Sub-problems that are not solved due to pruning should not appear in the table.