For C++ 17 version of KLFM algorithm implementation, see github
KLFM stands for Kernighan-Lin Fiduccia-Mattheyses, and it's in fact most popular C++ graph by-partitioning algoritm
It was first introduced in 1982, original paper "A Linear-Time Heuristic for Improving Network Partitions" [1]
One of the best known implementations is provided as part as MLPART package, developed by prof. Andrew Kahng research group in 1999 [2]
Outdated: Less complex and simple C++98 implementation was developed and published in 2015 on SourceForge Source code