A factory needs to allocate resources to produce metal rods. The production of each rod requires a cylindrical piece of metal with a volume of 100 cubic centimeters. The factory has a total of 5000 cubic centimeters of metal available. If the production efficiency is such that for every 10 units of volume used, 1 unit is wasted, how many rods can the factory produce? Let's think step by step and output the final answer within \boxed{}.
user