[CS 61A SU26] Ants Problem Getting Started

[00:00:02]hey and welcome to problem 2 on the ants project so in this problem we do not complete the inner Constructor for the place class and uh sort of what uh this place class really is is like each set of uh position in this diagram here it can be considered a place and every place has an exit and then an entrance over here so uh the exit is sort of the the place that occurs before the the current place that we're looking at and then the entrance is sort of the place after that right after that um So currently if you look at the python file you see that a place only keeps track of its exit value but we also want the place to keep track of the entrance uh so every place has one entrance for that matter and this will be useful later on in the project so it's a super important sort of problem to work on uh and basically the reason why this problem is not as simple as it seems is because uh when we just pass in an entrance to the place Constructor uh this would be a bit of an issue because let's say it's like place number eight over here if we try to pass an entrance to that uh we need the entrance as well as the exit from before like while creating the place but that is a problem because when we create a new place here we don't really have the entrance already existing like there's nothing to the right of that and and so that's why it's sort of like it shaking on the ad problem of like which comes first um but don't worry like we have a solution to that and to get around this what we're gonna do is uh use this logic so in the init function we kind of automatically set the entrance of the place as none uh but what we do after that is if the place has an exit so if exit is not equal to none then the exits entrance so we go into the exit and then set the entrance value equal to place uh so that's sort of how we do it so like if it's Place three for example we're currently the turn object is Place three uh we start with the entrance of place three as none but then between Place three has an edge set which is place number two um we set the exits entrance so the edge the entrance of place number two we set it to place three so we can go back one spot and then set the entrance to the current object that we have uh a few hints one is that when the init method is called summary Constructor for class is called uh the first parameter which itself is always sort of referring to the newly created objects like your current object that you're creating um and another thing is that the places aren't really stored in the list so you don't really like index something to access the places or to like access the neighboring places uh so how can you sort of move from one place to another and and to kind of just give a little bit of a hint like if you look at the place loss in in the python file uh there's a few things that we need to do one thing is like we automatically set the entrance here to none which is totally fine as per the problem although the next thing we need to do within here is kind of go to the exit and then set the entrance of the exit to the current place so uh as we talked about earlier you can find the current place by using the self parameter so that's one thing and the other thing is if um the place has an edge so if self-directed is not equal to none uh then how can you set the entrance of self.edzit uh to the current place so if we have the torrent Place itself how do we access the entrance of the self.edzer so think about how you sort of access later attribute of an object like how we've been doing it before and maybe try to use that to kind of solve this problems so it's actually not a very difficult problem we can do it in one or two lines of code maybe or or like in a pretty short piece of code so I'll think about how you can access the entrance of the uh current objects exit and then set the entrance equal to the turn object which is uh as you as we've seen before uh is probably referred to by by itself uh so yeah good luck on problem two hopefully that made sense uh thank you