My current project features a set of nodes with inputs and outputs. Each node can take its input values and generate some output values. Those outputs can be used as inputs for other nodes. To minimize the amount of computation needed, node dependencies are checked on application start. When updating the nodes, they are updated in the reverse order they depend on each other.
That said, the nodes resemble a directed graph. I am using iterative DFS (no recursion to avoid stack overflows in huge graphs) to work out the dependencies and create an order for updating the nodes.
I further want to avoid cycles in a graph because cyclic dependencies will break the updater algorithm and causing a forever running loop.
There are recursive approaches to finding cycles with DFS by tracking nodes on the recursion stack, but is there a way to do it iteratively? I could then embed the cycle search in the main dependency resolver to speed things up.