arrays - PHP Given increasing numbers in this order, calculate all possible combinations -

-

the problem simple, giving me headache, have example 4 numbers array, can have 20 numbers. given in following order:

       [1]  [2]  [4]  [5]

i need obtain combinations of numbers, except numbers can't permuted, order maintained, i'll give example of i'm trying obtain:

     [1] [ ] [4] [5]      [1] [2] [ ] [5]      [ ] [2] [4] [5]      [ ] [ ] [ ] [5]      ,      [ ] [ ] [ ] [ ]

the resulting array contain sub arrays of resulting numbers

update: empty arrays optional, 

          [1] [4]                  or             [2] [4] [5]

would ok also, less complications.

what want can done quite easily, if realize want accomplish in fact recursive. each subpart need make choice: add space, or add number our list.

function wonkypermutations( $numbers ) {   return wonkypermutationswithspaces( array(), $numbers, count( $numbers ) ); }  function wonkypermutationswithspaces( $prefix, $numbers, $maxlength ) {   if( $maxlength == 0 ) {     //we can't add anymore     return array( $prefix );   } else {     //we have 2 choices: either add space, or don't.     $prefix1 = $prefix;     $prefix1[] = null;     $prefix2 = $prefix;     $prefix2[] = $numbers[0];     $suffix1 = wonkypermutationswithspaces( $prefix1, array_slice( $numbers, 1 ), $maxlength - 1 );     $suffix2 = wonkypermutationswithspaces( $prefix2, array_slice( $numbers, 1 ), $maxlength - 1 );      return array_merge( $suffix1, $suffix2 );   } }  $a = array( 1, 2, 3, 4 ); var_dump( wonkypermutations( $a ) );

Comments

Post a Comment

Popular posts from this blog

javascript - Slick Slider width recalculation -

-
i'm trying add slide in panel on slick container css. carousel works except new width not being calculated when space has been added. recalibrate once advance next slide i'd happen each time panel opened or closed. i've tried adding both margin , padding, neither makes difference. ideas? https://jsfiddle.net/mhigley/dpf7mlpl/ html: <button type="button" id="button"><i class="fa fa-arrow-right"></i></button> <aside> <h2>slide in panel</h2> <ol> <li>list item</li> <li>list item</li> <li>list item</li> <li>list item</li> <li>list item</li> </ol> </aside> <main role="main"> <div class="sections"> <section> <article> <h2>first slide</h2> <p>lorem ipsum d...
Read more

jsf - PrimeFaces Datatable - What is f:facet actually doing? -

-
looking through primefaces code in app noticed following line: <f:facet name="header">#{trainsearch.traincount} trains</f:facet> it looks overriding header, makes sense, can explain me in little more detail? what happening line of code? complete code listed below: <p:datatable id = "results" value = "#{trainsearch.trains}" var = "train" rendered="#{not empty trainsearch.trains}" styleclass = "train-search-table horizontal-border"> <f:facet name="header">#{trainsearch.traincount} trains</f:facet> <p:column headertext = "train id"> <p:panelgrid columns="1" styleclass = "train-id-grid" layout = "grid"> <h:outputtext styleclass = "train-id-label" value="#{train.traini}"/> <h:outputtex...
Read more

angular2 services - Angular 2 RC 4 Http post not firing -

-
i trying fire post request app , it's not working, tried multiple ways. don't see request being fired under network tab in chrome. not sure problem is, appreciated. import { injectable } '@angular/core'; import { http, headers } '@angular/http'; @injectable() export class userservice{ private _url="users"; constructor(private _http: http){ } checkifusernameexists(username){ return this._http.get(this._url+"/"+username) .map(response => response.json()) } createuser(user){ let headers = new headers(); headers.append('content-type', 'application/json') console.log(json.stringify(user)); return this._http.post(this._url, json.stringify(user),{headers: headers}) .map(response => response.json()) } } first need capture error , solve error: this._http.post(this._url, json.stringify(user),{headers: headers}) .subscribe( ...
Read more