How to generate all possibilities of a string with X tokens and Y values for each token
So, I have a template string with X amount of tokens in it. Hypothetically it could look like this:
template = "render=@layer0@-@layer1@-@layer2@-@layer3@-@layer4@"
The token开发者_Go百科s, obviously, take the form of @tokenname@
. In this hypothetical case it has five tokens. Each token has a different set of possible values. For example:
token0Values = ['t0value1'];
token1Values = ['t1value1','t1value2'];
token2Values = ['t2value1','t2value2','t2value3'];
token3Values = ['t3value1','t3value2'];
token4Values = ['t4value1','t4value2','t4value3','t4value4'];
My question then is, how do I generate every possible permutation of the string given the template and the possible values for each token?
I'll take a stab at it in sorta php/AS
tokens is a two dimensional array of possible values
{ [0] = "apple","banana","pear" [1] = "carrot","pea" [2] = "potato", "celery", "butter","gravy" }
function getPermutations(tokens){
var perms = array();
//exit condition : there's only one token;
//total permutations = values array
//so just return it
if (tokens.length == 1)
return tokens[0];
//otherwise
//strip 1st element of the array as your "prefix"
prefices= tokens.shift();
//get the permuations of the children
childPermutations = getPermutations(tokens);
//loop through the possible values, or "prefices"
foreach (prefices as prefix){
//concatenate to each of the child permutations
foreach(childPermutations as perm)
perms[]=prefix + perm;
}
//return the glob
return perms;
}
that might work, or something similar
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