I've got a grid alike structure, in which there are on maximum 4 portals (exits) around each cluster... I found that sometimes the algorithm never terminates such as on this structure where
I want to travel from cluster 3 to 9

Big Box:=====>
id: 0min x: -40.5623 y:-0.0923912 z:-40.0071 max x: -23.2048 y:-0.0923912 z:-24.0042 12 neis size:2
Big Box:=====>
id: 1min x: -40.5623 y:-0.0923912 z:-24.0042 max x: -23.2048 y:-0.0923912 z:-8.00142 0 neis size:4
Big Box:=====>
id: 2min x: -40.5623 y:-0.0923912 z:-8.00142 max x: -23.2048 y:-0.0923912 z:8.00141 3 neis size:4
Big Box:=====>
id: 3min x: -40.5623 y:-0.0923912 z:8.00141 max x: -23.2048 y:-0.0923912 z:24.0042 4 neis size:4
Big Box:=====>
id: 4min x: -40.5623 y:-0.0923912 z:24.0042 max x: -23.2048 y:-0.0923912 z:40.0071 4 neis size:3
Big Box:=====>
id: 5min x: -23.2048 y:-0.0923912 z:-40.0071 max x: -5.84741 y:-0.0923912 z:-24.0042 17 neis size:2
Big Box:=====>
id: 6min x: -23.2048 y:-0.0923912 z:-24.0042 max x: -5.84741 y:-0.0923912 z:-8.00142 0 neis size:4
Big Box:=====>
id: 7min x: -23.2048 y:-0.0923912 z:-8.00142 max x: -5.84741 y:-0.0923912 z:8.00141 1 neis size:4
Big Box:=====>
id: 8min x: -23.2048 y:-0.0923912 z:8.00141 max x: -5.84741 y:-0.0923912 z:24.0042 0 neis size:4
Big Box:=====>
id: 9min x: -23.2048 y:-0.0923912 z:24.0042 max x: -5.84741 y:-0.0923912 z:40.0071 3 neis size:3
Big Box:=====>
id: 10min x: -5.84741 y:-0.0923912 z:-40.0071 max x: 11.51 y:-0.0923912 z:-24.0042 12 neis size:2
Big Box:=====>
id: 11min x: -5.84741 y:-0.0923912 z:-24.0042 max x: 11.51 y:-0.0923912 z:-8.00142 0 neis size:4
Big Box:=====>
id: 12min x: -5.84741 y:-0.0923912 z:-8.00142 max x: 11.51 y:-0.0923912 z:8.00141 0 neis size:4
Big Box:=====>
id: 13min x: -5.84741 y:-0.0923912 z:8.00141 max x: 11.51 y:-0.0923912 z:24.0042 0 neis size:4
Big Box:=====>
id: 14min x: -5.84741 y:-0.0923912 z:24.0042 max x: 11.51 y:-0.0923912 z:40.0071 5 neis size:3
Big Box:=====>
id: 15min x: 11.51 y:-0.0923912 z:-40.0071 max x: 28.8675 y:-0.0923912 z:-24.0042 12 neis size:2
Big Box:=====>
id: 16min x: 11.51 y:-0.0923912 z:-24.0042 max x: 28.8675 y:-0.0923912 z:-8.00142 0 neis size:4
Big Box:=====>
id: 17min x: 11.51 y:-0.0923912 z:-8.00142 max x: 28.8675 y:-0.0923912 z:8.00141 3 neis size:4
Big Box:=====>
id: 18min x: 11.51 y:-0.0923912 z:8.00141 max x: 28.8675 y:-0.0923912 z:24.0042 31 neis size:4
Big Box:=====>
id: 19min x: 11.51 y:-0.0923912 z:24.0042 max x: 28.8675 y:-0.0923912 z:40.0071 4 neis size:3
Big Box:=====>
id: 20min x: 28.8675 y:-0.0923912 z:-40.0071 max x: 46.2249 y:-0.0923912 z:-24.0042 1 neis size:1
Big Box:=====>
id: 21min x: 28.8675 y:-0.0923912 z:-24.0042 max x: 46.2249 y:-0.0923912 z:-8.00142 3 neis size:3
Big Box:=====>
id: 22min x: 28.8675 y:-0.0923912 z:-8.00142 max x: 46.2249 y:-0.0923912 z:8.00141 8 neis size:3
Big Box:=====>
id: 23min x: 28.8675 y:-0.0923912 z:8.00141 max x: 46.2249 y:-0.0923912 z:24.0042 0 neis size:3
Big Box:=====>
id: 24min x: 28.8675 y:-0.0923912 z:24.0042 max x: 46.2249 y:-0.0923912 z:40.0071 5 neis size:2

I haven't implemented one of these myself yet, but I see cycles shown in the examples on the https://en.wikipedia.org/wiki/Edmonds–Karp_algorithm page (a specific implementation of the method you mentioned).

I'm not quite sure how to interpret your printout as a graph, though.

Okay, I sub it that algorithm for the max-flow part, the result is 10, did it look pretty right? each edge costs 5
thanks
Jack

I'm not very familiar with maximum flow.  What I would do to verify an algorithm is come up with a few test cases that you know how to compute by hand, and then make sure your code produces the same results.  You could use unit testing for that.