Question

I’ve created a node class and a tree class. From main, I call suffixTree t = new suffixTree(string); It is on a while loop so it will always be variable t.

The problem is, I want to read an input file and create a new tree for each string. Apparently, it won’t create a new instance.

The variable “t” is the same in each interaction but it should be a new instance everytime it creates it. The tree constructor, has a Node root = new Node();

It is a copied code, the only thing I did was to read from input and traverse the tree.

The problem is, if I type mississippi$ then acacdcacd$ it adds to the same tree and give a wrong result as I traverse it.

Thanks in advance

Answer 1

You are creating new instances but you are discarding them right after creation because they are not stored anywhere and as such they are unreachable and marked as ready for garbage collection.

have a look at the following:

// this is where the SuffixTree instances will end up
List<SuffixTree> suffixes = new ArrayList<SuffixTree>();


String[] strings = new String[3];
for (String string : strings) {
    // A new suffix tree is created here but if you don't do anything
    // with it then it is marked as garbage collectable when the closed
    // curly brace is reached
    SuffixTree t = new SuffixTree(string);


    // Now I'm pushing the object into the suffixes list: this will prevent
    // the loss of the object currently stored in the t variable
    suffixes.add(t);
}