• Status: Solved
  • Priority: Medium
  • Security: Public
  • Views: 79
  • Last Modified:

javascript optimization on finding substrings

Hi Experts,

I have one string S that can be say, 200 characters long.   I have 10000 other strings that I want to see if they are in S.

My solution needs to work on IE9, IE10, IE11, Firefox and chrome.  I would preferably not like to use one method on one browser and another method for special case browsers that don't support functions.

What can I use to optimize this?

Thanks a lot!
Mike
0
thready
Asked:
thready
2 Solutions
 
James BilousSoftware EngineerCommented:
The Knuth-Morris-Pratt algorithm is pretty quick and is O(S). That's about as good as you're going to get without getting overly complicated. You'll probably need to implement it in JS yourself.

algorithm kmp_search:
    input:
        an array of characters, S (the text to be searched)
        an array of characters, W (the word sought)
    output:
        an integer (the zero-based position in S at which W is found)

    define variables:
        an integer, m ← 0 (the beginning of the current match in S)
        an integer, i ← 0 (the position of the current character in W)
        an array of integers, T (the table, computed elsewhere)

    while m + i < length(S) do
        if W[i] = S[m + i] then
            if i = length(W) - 1 then
                return m
            let i ← i + 1
        else
            if T[i] > -1 then
                let m ← m + i - T[i], i ← T[i]
            else
                let i ← 0, m ← m + 1
            
    (if we reach here, we have searched all of S unsuccessfully)
    return the length of S

Open in new window

0
 
zzynxSoftware engineerCommented:
FYI: You'd better not tagged this question as a Java Programming language question.
Java and JavaScript are two different languages.
0
 
Slick812Commented:
greetings thready, , Not sure about exact nature of what you describe as "to see if they are in S", If all you need is a return of "TRUE" if array value IS in string, Then I believe that the -
for (s=0; s < seek.length; ++s)
    if (str.indexOf(seek[s]) > -1) found[s] = true; else found[s] = false;

would be the most effective.
 I found this in the AJAX section, not sure I see any reference to a server side response here? ?
0
 
threadyAuthor Commented:
Thanks a lot for your answers!
0

Featured Post

Get your problem seen by more experts

Be seen. Boost your question’s priority for more expert views and faster solutions

Tackle projects and never again get stuck behind a technical roadblock.
Join Now