How do I use the Edmonds-Karp algorithm to calculate the maximum flow? I don't understand this algorithm $100\%$. What I need to know is about flow with minus arrow. Here is my graph:
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Our $1-6-11-12$, the flow is $4$. On the next iteration $1-2-4-11-6-7-9-12$, the flow on $6-11$ decrease on $3$, on other $+3$ on how do next? $1-3-5-11-6-8-10-12$? What will be with $11-6$? We must take $-3$, we will get negative flow on $6-11$ or what? Help me please.