Corrections

1) In the Lecture note it was written that Traveling salesperson problem was NP, it is as formulated in the lecture NP-Hard  (in some discrete formulations it is NP-complete) 

2) The code which shows the local search "Greedy" in ex 3.1, can be regarded as "too greedy". It updates the parameter at once when it finds an improvement, rather than searching through complete the neighborhood first. I have added code that does the search of the complete neighborhood first for comparison.