External Issue: Set

17214, "zhihuidu", "Set ", "2021-02-20T15:34:52Z"

Summary of Problem

What behavior did you observe when encountering this issue?
When I use set to keep the frontier vertices in breadth first search (BFS) algorithm, for a special line graph, the program with 2 locales will break down. However, When I use Domain or DistBag to keep the vertices, no errors happen.

The delaunay benchmark will cause the same error too.

Steps to Reproduce

Source Code:
The BFS codes can be accessed here

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Execution command:
The server side will start an arkouda like this
./arkouda_server -nl 2

the client side is like this
python bfs.py nodexx 5555

If an input file is required, include it as well. -->
The line graph is just like this
0 1
1 2
2 3
3 4
4 5
5 6
999 1000