Self loops in max flow problem So, there can be different types of edges in a directed graph while solving the max flow problem. There can be reverse edges, multiple edges and self loops. 

What is the significance of self loops in it? 

How is it related to flow in the graph?

Let there be a graph like this 1-&gt;2-&gt;3 and 2 has a self loop. So, can I interpret it like this-

1-&gt;2a--2b-&gt;3 ? where -- denotes an edge from 2a-&gt;2b and an edge from 2b-&gt;2a. 

So, How would I represent this in a graph using adjacency list?
for the max flow problem you should remove the self loops and solve it. self loops don't effect on final solution because when there exists a loop on a vertex, it means a flow from the vertex (with an arbitrary capacity) goes on pipe that connect to itself, it means the flow doesn't waste, it just return to the vertex. it's like you connect a water hose from a tank to itself. you don't limit the input flow to the tank or output flow from it. so you can ignore self loops and solve the problem.