Lec-24 Traveling Salesman Problem(TSP)

99 thoughts on “Lec-24 Traveling Salesman Problem(TSP)

  1. Can someone explain this – after branching off for example from X15 (with cost 31), how is he forming branches to X21, X23, X24? Since X15 is already fixed, shouldn't the next path only be from point 5 which is the destination reached? So the child branches from X15 should only be X52, X53, X54? Similar for X32 and others?

  2. Awesomeness level over 9000. You Sir are too good, explanation much better than the one done by my Prof. at Cal. State University

  3. @Sampath Krishnan yes you can do that. But you would have to solve all other branches for solution/elimination anyways. Essentially, you fix one path and find the shortest path based on the remainder matrix. In this respect, the node you start off for evaluation of the remainder matrix is your choice.

  4. thank you for the effort you put on this video. it really is gonna help me alot to perform well in the upcoming exams. I liked the way you clarified the algorithm and you made it look easy.

  5. @TheViniArya- it does not make sens. 
    When we already have 1-3 and we added tour 3 – 1 we create subtour, because every vertex have only one enterance and one exit, It means the tpur 1-3-1 is closed and does not have connection to other vertex.

    I can't get this. Once we consider about subtour once not.

  6. And the another question is about 49:00. 
    Why there are considered only two edges: 3 – 2 and 3 – 5, whereas 3-4 does not create a subtour?
    There are made edges: 1-3 and 2-4
    Adding edge 3-2 leads to 1-3-2-4, which is ok,
    adding edge 3-5 leads to 1-3-5, 2-4 which is also ok,
    adding edge 3-4 leads to 1-3-4-2 <- this is not ok? Why? The branch 2-5 and 5-1 can't be added?

  7. Loving this tutorial 🙂

    Came here just to learn the algorithm. Ended up really interested in the whole concept.

  8. Regards, great explanation, thank you for that. But I have two questions, first the significance of the variable U, and second as I can include inequality constraint that a program that handles linear models, for example Excel Solver. Thanks, again

  9. For students of Integer Constraints Programming there is an awesome app on Android Play store https://play.google.com/store/apps/details?id=in.co.boilerplate.solver . It provides a SCARTCH like programming environment to model constraints. I am the author.

  10. sir good but i have a doubt at starting point you are saying that sum of i=1 to n but actually it is i=1 to n-1 because (n-1)! possible ways.since each city  visit only once so sum of i=1 to n-1 xij value is equal to 0 where i not equal to j and j =1,2,3,….n

  11. hello…
    how to write programs using HEAPSORT to
    solve Travelling Salesman Problem – TSP on programming language C …
    and I need code 🙁
    im form Viet Nam…thanks

  12. Would appreciate help: Minute 26, subtour elimination, i is from 1 to n-1 (=5-1=4), but he uses U5…
    If he would have done it according to i=1…n-1, j=2…n, the second subtour would be one equation that satisfies U4-U5+5<=4
    + I read that U stands for sequence in the tour, is that right???

  13. I know next to nothing about math and found this perfectly clear. Wish I had teachers like you when I was in school — then I probably would know more than nothing about math now.

  14. The Ui – Uj constraint corresponds to the formulation proposed by Tucker and Miller in 1960. It is defined for i,j >=2….n, and i<>j. A small mistake, but this guy is awesome.

  15. How come around 40:00 we go from X15 to X23? Doesn't that imply that the path is 1-5-2-3? Shouldn't we be checking X53 instead?

  16. According to the wiki of TSP https://en.wikipedia.org/wiki/Travelling_salesman_problem . In the subtours elimination the i starts from 2. The professor wrote it correectly so now I am able to understand this constraints.

  17. Why we need to eliminate subtours ? In the problem if we are starting from some vertex then we have to reach to that vertex so why we need to eliminate subtours ?

  18. Great video, especially from 30:00 onward. Went through every step, with no skipping. Perfect for learning this algorithm.

  19. 26:40 How come professor wrote "U5 – U4 + 5 <= 4".
    As according to the condition "i" can only take values from 1 to n-1 and here U5 indicate that i has been taken as 5.

  20. Most of the lectures on this problem were just talking without real results but this one is totaly different thank you for ur offerts

Leave a Reply

Your email address will not be published. Required fields are marked *