Exercise 3 (Due 09.12.2025)

All documents we mentioned can be found in folder “Mechsystem”.

In this part, we solve problem:

• 20.4

We write many details to show results step by step (including codes). But in the report, just mention main thing.

For more complete codes, we have already uploaded in mechsystem folder.

Basiclly, we have changed:
1. *mass_spring_hpp* -- add the constraints 
2. *bind_mass_spring.cpp* -- connect cpp with pybind
3. *Newmark.hpp* -- increase the tolerance and max iteration to get better result