Why CLRS example on residual networks does not follows its formula? The 2019 Stack Overflow Developer Survey Results Are InWhy is the complexity of negative-cycle-cancelling $O(V^2AUW)$?CLRS - Maxflow Augmented Flow Lemma 26.1 - don't understand use of def. in proofFord-Fulkerson algorithm clarificationLinear programming formulation of cheapest k-edge path between two nodesWhy is it that the flow value can increased along an augmenting path $p$ in a residual network?Maximum flow with Edmonds–Karp algorithmHow would one construct conjunctively local predicate of order k for checking if a shape is Convex?Equivalence of minimum cost circulation problem and minimum cost max flow problemGiven max-flow determine if edge is in a min-cutWhat is the intuition behind the way of reading off a dual optimal solution from simplex primal tabular in CLRS?

Are there any other methods to apply to solving simultaneous equations?

For what reasons would an animal species NOT cross a *horizontal* land bridge?

If I score a critical hit on an 18 or higher, what are my chances of getting a critical hit if I roll 3d20?

How do PCB vias affect signal quality?

What is the motivation for a law requiring 2 parties to consent for recording a conversation

What is this business jet?

Why not take a picture of a closer black hole?

Deal with toxic manager when you can't quit

Why can't devices on different VLANs, but on the same subnet, communicate?

Why doesn't UInt have a toDouble()?

What do these terms in Caesar's Gallic Wars mean?

writing variables above the numbers in tikz picture

Likelihood that a superbug or lethal virus could come from a landfill

Is it ethical to upload a automatically generated paper to a non peer-reviewed site as part of a larger research?

A word that means fill it to the required quantity

How much of the clove should I use when using big garlic heads?

Can an undergraduate be advised by a professor who is very far away?

Ubuntu Server install with full GUI

Is Cinnamon a desktop environment or a window manager? (Or both?)

Why don't hard Brexiteers insist on a hard border to prevent illegal immigration after Brexit?

Can you cast a spell on someone in the Ethereal Plane, if you are on the Material Plane and have the True Seeing spell active?

How do you keep chess fun when your opponent constantly beats you?

How come people say “Would of”?

Did Scotland spend $250,000 for the slogan "Welcome to Scotland"?



Why CLRS example on residual networks does not follows its formula?



The 2019 Stack Overflow Developer Survey Results Are InWhy is the complexity of negative-cycle-cancelling $O(V^2AUW)$?CLRS - Maxflow Augmented Flow Lemma 26.1 - don't understand use of def. in proofFord-Fulkerson algorithm clarificationLinear programming formulation of cheapest k-edge path between two nodesWhy is it that the flow value can increased along an augmenting path $p$ in a residual network?Maximum flow with Edmonds–Karp algorithmHow would one construct conjunctively local predicate of order k for checking if a shape is Convex?Equivalence of minimum cost circulation problem and minimum cost max flow problemGiven max-flow determine if edge is in a min-cutWhat is the intuition behind the way of reading off a dual optimal solution from simplex primal tabular in CLRS?










1












$begingroup$


I am learning algorithms to solve Maximum Flow problem by reading the CRLS book and confused by the following figure:



figure 26.4



That is:




A flow in a residual network provides a roadmap for adding flow to the
original flow network. If $f$ is a flow in $G$ and $f'$ is a flow in
the corresponding residual network $G_f$, we define $f uparrow f'$,
the augmentation of flow $f$ by $f'$, to be a function from $V times V$ to
$R$, defined by



$$(f uparrow f')(u, v) = begincases f(u,v) + f'(u, v) - f'(v, u) &
> textif (u,v) $in$ E \ 0 & textotherwise endcases$$




How the flow network in (c), for example $(s, v_2)$ got the flow 12 ?
If we follow the formula, it must have a flow 5:
$8 + 5 - 8 = 5$










share|cite|improve this question









$endgroup$
















    1












    $begingroup$


    I am learning algorithms to solve Maximum Flow problem by reading the CRLS book and confused by the following figure:



    figure 26.4



    That is:




    A flow in a residual network provides a roadmap for adding flow to the
    original flow network. If $f$ is a flow in $G$ and $f'$ is a flow in
    the corresponding residual network $G_f$, we define $f uparrow f'$,
    the augmentation of flow $f$ by $f'$, to be a function from $V times V$ to
    $R$, defined by



    $$(f uparrow f')(u, v) = begincases f(u,v) + f'(u, v) - f'(v, u) &
    > textif (u,v) $in$ E \ 0 & textotherwise endcases$$




    How the flow network in (c), for example $(s, v_2)$ got the flow 12 ?
    If we follow the formula, it must have a flow 5:
    $8 + 5 - 8 = 5$










    share|cite|improve this question









    $endgroup$














      1












      1








      1





      $begingroup$


      I am learning algorithms to solve Maximum Flow problem by reading the CRLS book and confused by the following figure:



      figure 26.4



      That is:




      A flow in a residual network provides a roadmap for adding flow to the
      original flow network. If $f$ is a flow in $G$ and $f'$ is a flow in
      the corresponding residual network $G_f$, we define $f uparrow f'$,
      the augmentation of flow $f$ by $f'$, to be a function from $V times V$ to
      $R$, defined by



      $$(f uparrow f')(u, v) = begincases f(u,v) + f'(u, v) - f'(v, u) &
      > textif (u,v) $in$ E \ 0 & textotherwise endcases$$




      How the flow network in (c), for example $(s, v_2)$ got the flow 12 ?
      If we follow the formula, it must have a flow 5:
      $8 + 5 - 8 = 5$










      share|cite|improve this question









      $endgroup$




      I am learning algorithms to solve Maximum Flow problem by reading the CRLS book and confused by the following figure:



      figure 26.4



      That is:




      A flow in a residual network provides a roadmap for adding flow to the
      original flow network. If $f$ is a flow in $G$ and $f'$ is a flow in
      the corresponding residual network $G_f$, we define $f uparrow f'$,
      the augmentation of flow $f$ by $f'$, to be a function from $V times V$ to
      $R$, defined by



      $$(f uparrow f')(u, v) = begincases f(u,v) + f'(u, v) - f'(v, u) &
      > textif (u,v) $in$ E \ 0 & textotherwise endcases$$




      How the flow network in (c), for example $(s, v_2)$ got the flow 12 ?
      If we follow the formula, it must have a flow 5:
      $8 + 5 - 8 = 5$







      algorithms network-flow






      share|cite|improve this question













      share|cite|improve this question











      share|cite|improve this question




      share|cite|improve this question










      asked Apr 7 at 15:52









      maksadbekmaksadbek

      1185




      1185




















          2 Answers
          2






          active

          oldest

          votes


















          4












          $begingroup$

          That's not what the formula gives you. As the caption says, the capacity of the augmenting path in the residual network in (b) is $4$. Therefore we send 4 units of flow along the augmenting path from $s$ to $t$, namely, the path $s to v_2 to v_3 to t$. In particular, $f(s,v_2)=8$, $f'(s,v_2)=4$, and $f'(v_2,s)=0$, so the updated flow is $8+4-0=12$.






          share|cite|improve this answer









          $endgroup$




















            3












            $begingroup$

            It is explained in part (b) of the caption of Figure 26.4.




            The residual network $G_f$ with augmenting path $p$ shaded; its residual capacity is $c_f(p)=c_f(v_2,v_3)=4$.




            Since the capacity of path $p$ is 4 (not 5), we find a flow $f'$ in the residual network $G_f$ that is defined by $f'(s,v_2)=f'(v_2,v_3)=f'(v_3,t)=4$. So for the network flow $fuparrow f'$ in (c), we have
            $$ (fuparrow f')(v_2, v_3)=f(v_2,v_3)+f'(v_2,v_3) = 8+4=12.$$






            share|cite|improve this answer











            $endgroup$













              Your Answer





              StackExchange.ifUsing("editor", function ()
              return StackExchange.using("mathjaxEditing", function ()
              StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix)
              StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
              );
              );
              , "mathjax-editing");

              StackExchange.ready(function()
              var channelOptions =
              tags: "".split(" "),
              id: "419"
              ;
              initTagRenderer("".split(" "), "".split(" "), channelOptions);

              StackExchange.using("externalEditor", function()
              // Have to fire editor after snippets, if snippets enabled
              if (StackExchange.settings.snippets.snippetsEnabled)
              StackExchange.using("snippets", function()
              createEditor();
              );

              else
              createEditor();

              );

              function createEditor()
              StackExchange.prepareEditor(
              heartbeatType: 'answer',
              autoActivateHeartbeat: false,
              convertImagesToLinks: false,
              noModals: true,
              showLowRepImageUploadWarning: true,
              reputationToPostImages: null,
              bindNavPrevention: true,
              postfix: "",
              imageUploader:
              brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
              contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
              allowUrls: true
              ,
              onDemand: true,
              discardSelector: ".discard-answer"
              ,immediatelyShowMarkdownHelp:true
              );



              );













              draft saved

              draft discarded


















              StackExchange.ready(
              function ()
              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcs.stackexchange.com%2fquestions%2f106608%2fwhy-clrs-example-on-residual-networks-does-not-follows-its-formula%23new-answer', 'question_page');

              );

              Post as a guest















              Required, but never shown

























              2 Answers
              2






              active

              oldest

              votes








              2 Answers
              2






              active

              oldest

              votes









              active

              oldest

              votes






              active

              oldest

              votes









              4












              $begingroup$

              That's not what the formula gives you. As the caption says, the capacity of the augmenting path in the residual network in (b) is $4$. Therefore we send 4 units of flow along the augmenting path from $s$ to $t$, namely, the path $s to v_2 to v_3 to t$. In particular, $f(s,v_2)=8$, $f'(s,v_2)=4$, and $f'(v_2,s)=0$, so the updated flow is $8+4-0=12$.






              share|cite|improve this answer









              $endgroup$

















                4












                $begingroup$

                That's not what the formula gives you. As the caption says, the capacity of the augmenting path in the residual network in (b) is $4$. Therefore we send 4 units of flow along the augmenting path from $s$ to $t$, namely, the path $s to v_2 to v_3 to t$. In particular, $f(s,v_2)=8$, $f'(s,v_2)=4$, and $f'(v_2,s)=0$, so the updated flow is $8+4-0=12$.






                share|cite|improve this answer









                $endgroup$















                  4












                  4








                  4





                  $begingroup$

                  That's not what the formula gives you. As the caption says, the capacity of the augmenting path in the residual network in (b) is $4$. Therefore we send 4 units of flow along the augmenting path from $s$ to $t$, namely, the path $s to v_2 to v_3 to t$. In particular, $f(s,v_2)=8$, $f'(s,v_2)=4$, and $f'(v_2,s)=0$, so the updated flow is $8+4-0=12$.






                  share|cite|improve this answer









                  $endgroup$



                  That's not what the formula gives you. As the caption says, the capacity of the augmenting path in the residual network in (b) is $4$. Therefore we send 4 units of flow along the augmenting path from $s$ to $t$, namely, the path $s to v_2 to v_3 to t$. In particular, $f(s,v_2)=8$, $f'(s,v_2)=4$, and $f'(v_2,s)=0$, so the updated flow is $8+4-0=12$.







                  share|cite|improve this answer












                  share|cite|improve this answer



                  share|cite|improve this answer










                  answered Apr 7 at 17:50









                  D.W.D.W.

                  103k12129294




                  103k12129294





















                      3












                      $begingroup$

                      It is explained in part (b) of the caption of Figure 26.4.




                      The residual network $G_f$ with augmenting path $p$ shaded; its residual capacity is $c_f(p)=c_f(v_2,v_3)=4$.




                      Since the capacity of path $p$ is 4 (not 5), we find a flow $f'$ in the residual network $G_f$ that is defined by $f'(s,v_2)=f'(v_2,v_3)=f'(v_3,t)=4$. So for the network flow $fuparrow f'$ in (c), we have
                      $$ (fuparrow f')(v_2, v_3)=f(v_2,v_3)+f'(v_2,v_3) = 8+4=12.$$






                      share|cite|improve this answer











                      $endgroup$

















                        3












                        $begingroup$

                        It is explained in part (b) of the caption of Figure 26.4.




                        The residual network $G_f$ with augmenting path $p$ shaded; its residual capacity is $c_f(p)=c_f(v_2,v_3)=4$.




                        Since the capacity of path $p$ is 4 (not 5), we find a flow $f'$ in the residual network $G_f$ that is defined by $f'(s,v_2)=f'(v_2,v_3)=f'(v_3,t)=4$. So for the network flow $fuparrow f'$ in (c), we have
                        $$ (fuparrow f')(v_2, v_3)=f(v_2,v_3)+f'(v_2,v_3) = 8+4=12.$$






                        share|cite|improve this answer











                        $endgroup$















                          3












                          3








                          3





                          $begingroup$

                          It is explained in part (b) of the caption of Figure 26.4.




                          The residual network $G_f$ with augmenting path $p$ shaded; its residual capacity is $c_f(p)=c_f(v_2,v_3)=4$.




                          Since the capacity of path $p$ is 4 (not 5), we find a flow $f'$ in the residual network $G_f$ that is defined by $f'(s,v_2)=f'(v_2,v_3)=f'(v_3,t)=4$. So for the network flow $fuparrow f'$ in (c), we have
                          $$ (fuparrow f')(v_2, v_3)=f(v_2,v_3)+f'(v_2,v_3) = 8+4=12.$$






                          share|cite|improve this answer











                          $endgroup$



                          It is explained in part (b) of the caption of Figure 26.4.




                          The residual network $G_f$ with augmenting path $p$ shaded; its residual capacity is $c_f(p)=c_f(v_2,v_3)=4$.




                          Since the capacity of path $p$ is 4 (not 5), we find a flow $f'$ in the residual network $G_f$ that is defined by $f'(s,v_2)=f'(v_2,v_3)=f'(v_3,t)=4$. So for the network flow $fuparrow f'$ in (c), we have
                          $$ (fuparrow f')(v_2, v_3)=f(v_2,v_3)+f'(v_2,v_3) = 8+4=12.$$







                          share|cite|improve this answer














                          share|cite|improve this answer



                          share|cite|improve this answer








                          edited Apr 7 at 17:52

























                          answered Apr 7 at 17:51









                          Apass.JackApass.Jack

                          14.1k1940




                          14.1k1940



























                              draft saved

                              draft discarded
















































                              Thanks for contributing an answer to Computer Science Stack Exchange!


                              • Please be sure to answer the question. Provide details and share your research!

                              But avoid


                              • Asking for help, clarification, or responding to other answers.

                              • Making statements based on opinion; back them up with references or personal experience.

                              Use MathJax to format equations. MathJax reference.


                              To learn more, see our tips on writing great answers.




                              draft saved


                              draft discarded














                              StackExchange.ready(
                              function ()
                              StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fcs.stackexchange.com%2fquestions%2f106608%2fwhy-clrs-example-on-residual-networks-does-not-follows-its-formula%23new-answer', 'question_page');

                              );

                              Post as a guest















                              Required, but never shown





















































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown

































                              Required, but never shown














                              Required, but never shown












                              Required, but never shown







                              Required, but never shown







                              Popular posts from this blog

                              Club Baloncesto Breogán Índice Historia | Pavillón | Nome | O Breogán na cultura popular | Xogadores | Adestradores | Presidentes | Palmarés | Historial | Líderes | Notas | Véxase tamén | Menú de navegacióncbbreogan.galCadroGuía oficial da ACB 2009-10, páxina 201Guía oficial ACB 1992, páxina 183. Editorial DB.É de 6.500 espectadores sentados axeitándose á última normativa"Estudiantes Junior, entre as mellores canteiras"o orixinalHemeroteca El Mundo Deportivo, 16 setembro de 1970, páxina 12Historia do BreogánAlfredo Pérez, o último canoneiroHistoria C.B. BreogánHemeroteca de El Mundo DeportivoJimmy Wright, norteamericano do Breogán deixará Lugo por ameazas de morteResultados de Breogán en 1986-87Resultados de Breogán en 1990-91Ficha de Velimir Perasović en acb.comResultados de Breogán en 1994-95Breogán arrasa al Barça. "El Mundo Deportivo", 27 de setembro de 1999, páxina 58CB Breogán - FC BarcelonaA FEB invita a participar nunha nova Liga EuropeaCharlie Bell na prensa estatalMáximos anotadores 2005Tempada 2005-06 : Tódolos Xogadores da Xornada""Non quero pensar nunha man negra, mais pregúntome que está a pasar""o orixinalRaúl López, orgulloso dos xogadores, presume da boa saúde económica do BreogánJulio González confirma que cesa como presidente del BreogánHomenaxe a Lisardo GómezA tempada do rexurdimento celesteEntrevista a Lisardo GómezEl COB dinamita el Pazo para forzar el quinto (69-73)Cafés Candelas, patrocinador del CB Breogán"Suso Lázare, novo presidente do Breogán"o orixinalCafés Candelas Breogán firma el mayor triunfo de la historiaEl Breogán realizará 17 homenajes por su cincuenta aniversario"O Breogán honra ao seu fundador e primeiro presidente"o orixinalMiguel Giao recibiu a homenaxe do PazoHomenaxe aos primeiros gladiadores celestesO home que nos amosa como ver o Breo co corazónTita Franco será homenaxeada polos #50anosdeBreoJulio Vila recibirá unha homenaxe in memoriam polos #50anosdeBreo"O Breogán homenaxeará aos seus aboados máis veteráns"Pechada ovación a «Capi» Sanmartín e Ricardo «Corazón de González»Homenaxe por décadas de informaciónPaco García volve ao Pazo con motivo do 50 aniversario"Resultados y clasificaciones""O Cafés Candelas Breogán, campión da Copa Princesa""O Cafés Candelas Breogán, equipo ACB"C.B. Breogán"Proxecto social"o orixinal"Centros asociados"o orixinalFicha en imdb.comMario Camus trata la recuperación del amor en 'La vieja música', su última película"Páxina web oficial""Club Baloncesto Breogán""C. B. Breogán S.A.D."eehttp://www.fegaba.com

                              Vilaño, A Laracha Índice Patrimonio | Lugares e parroquias | Véxase tamén | Menú de navegación43°14′52″N 8°36′03″O / 43.24775, -8.60070

                              Cegueira Índice Epidemioloxía | Deficiencia visual | Tipos de cegueira | Principais causas de cegueira | Tratamento | Técnicas de adaptación e axudas | Vida dos cegos | Primeiros auxilios | Crenzas respecto das persoas cegas | Crenzas das persoas cegas | O neno deficiente visual | Aspectos psicolóxicos da cegueira | Notas | Véxase tamén | Menú de navegación54.054.154.436928256blindnessDicionario da Real Academia GalegaPortal das Palabras"International Standards: Visual Standards — Aspects and Ranges of Vision Loss with Emphasis on Population Surveys.""Visual impairment and blindness""Presentan un plan para previr a cegueira"o orixinalACCDV Associació Catalana de Cecs i Disminuïts Visuals - PMFTrachoma"Effect of gene therapy on visual function in Leber's congenital amaurosis"1844137110.1056/NEJMoa0802268Cans guía - os mellores amigos dos cegosArquivadoEscola de cans guía para cegos en Mortágua, PortugalArquivado"Tecnología para ciegos y deficientes visuales. Recopilación de recursos gratuitos en la Red""Colorino""‘COL.diesis’, escuchar los sonidos del color""COL.diesis: Transforming Colour into Melody and Implementing the Result in a Colour Sensor Device"o orixinal"Sistema de desarrollo de sinestesia color-sonido para invidentes utilizando un protocolo de audio""Enseñanza táctil - geometría y color. Juegos didácticos para niños ciegos y videntes""Sistema Constanz"L'ocupació laboral dels cecs a l'Estat espanyol està pràcticament equiparada a la de les persones amb visió, entrevista amb Pedro ZuritaONCE (Organización Nacional de Cegos de España)Prevención da cegueiraDescrición de deficiencias visuais (Disc@pnet)Braillín, un boneco atractivo para calquera neno, con ou sen discapacidade, que permite familiarizarse co sistema de escritura e lectura brailleAxudas Técnicas36838ID00897494007150-90057129528256DOID:1432HP:0000618D001766C10.597.751.941.162C97109C0155020