I have a long string that contains data formatted in the following way:

var str = "parent /n /t child /n /t child /n /t /t grandchild /n parent";

If you print this out you get a tree structure like directories. I am trying to figure out a way/algorithm to individually extract every parent and child and children of the aforementioned and store them in an array for each of them so that I can access them later for other useful purposes. I was thinking of using a regular expression to extract the substrings since there is some sort of pattern but I am not an expert in that field and do not know if it is worth the time. Any other ways to approach this problem or is this the best way?


A child is always preceded with \n\t

A child's child "" "" "" \n\t\t (possibly spaces between the literals)

If the string is searched the substrings that have been searched should be stored somehow for compiling the node later.

  • 2
    $\begingroup$ I don't really understand what you're looking for. Scan the string until you reach one of the delimiters, then place whatever you just found into the tree in the appropriate place. $\endgroup$ – David Richerby Oct 10 '16 at 23:20

Don't use regexes. A tree is a recursively defined structure, and regexes don't do recursion (they can't match nested parens for the exact same reason).

You can easily build a tree structure by using a LIFO stack of nodes and maintaining an integer currentDepth, initially 0. For each line, pop nTabsAtStartOfLine - currentDepth - 1 nodes off the stack, create a new node, make it the child of the current top-of-stack, push it on the stack, and set currentDepth = nTabsAtStartOfLine.

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