Some doubts during using hpipm on Matlab

[CBUUU]

Hello Dr. Frison:
May I ask you some questions during using hpipm on Matlab? The questions are as follows.
1. In the file 'example_mass_spring_qp.m' , on the 228th line, why solver.solve run 100 times instead of once?
2. Are there any examples by using OCP_QP solver containing slack variables not equal to 0 ?
3. The hpipm c code is quite difficult to read ,such as 'how to use linear algebra library blasfeo',and confused in some algorithms about mpc. Do you have any suggestions to solve above troubles?

Best regards,
Chen