A naive implementation of Zenklusen's 1.5-approximation algorithm for the Path Traveling Salesman Problem.

The code is not very well organized.

If one wishes to make this code run in polynomial time, I believe the only adjustment to be made is how the linear programs are solved. They are now solved naively with their exponentially many constraints.

Based on this paper: https://epubs.siam.org/doi/abs/10.1137/1.9781611975482.93.