of maxflow jt

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Transcript of of maxflow jt

Applications of maxflow minent

edge disjointpaths jt Eyenetuork

vertex disjoint paths 1c f't

vertex capacities output max flew

bipartite maximum matchingcasualty integers

MaxMatching

Transform input features in solution F paths inTransform output Max flew

Time in terms oforiginalinputProve correct

Ex ling N ntr pt total input sizen classes Eft n enrollmentr rooms SCI r seatst timeslots Afa t t p availabilityp proctors ACKD T proctorL

is availableEvery class needs scheduling at EmekESS in any examEI exam per room per time slot

Ea.ch onoctoroverseesE5exam

class E capacityschedule set of 4 tuples i j k l room j g 1one per tindforkedavailable

1 or

do I f s

E I t

I

Each class EC jt exam EEthePIIIhas EI exam e inane Iet eachproctor can

exams

onh natch one

Feasibleexam atanytime

Integer flew 2 paths set of successfullyscheduled exams

IS Imax flow in H1 classes

ntr ftp.t2 OCNC En nr Http xp NZ

Time ONE 406USD

TnpleSelec_tionInp_tifinitesetsX1 Xe Xd

representdiscrete resources

for all x c Xi for all I

CCx y for all C Xi yExite for all

Outputtargetset of tuples Cx x xd cXzxXzx xXdSubject to constraints

for each index i each x c Xi appears in Edx tuplesfor each index i

each XE Xi and YE Xi I appear in Echr y tuples

MaxMatchinginput G LUR E X1 L

Outpt max matching Xz R

set of pairsCx y ELxR cC y1 if Xy EE0 if xy E

Ix Cly L

of yOFFIT 4

InX1 Xz Xd

largest complete complete complete maximumvalid set of tuples paths feasible flew

DisjointPat_hCoerTpnti gG Cv.ETgeneralgraphs NP hard

Output min disjointpaths that cover every vertex

b d0 30

08 1 0o oc e with

Intuition We want to assign a successor to as manymatch vertices as possible

a bb e

Iq Path.EE oFIYessorBuild

Reduce to max matching H LUR E

L U

R U Ccopyfind max matching.M

I0 0 paths in G

Oe s paths V M

0 VE timeV V

Projectselection Open pit mininginput dag Etv E U projects

C dependenciesprofit v U su means u can onlybedonefor every vertex after u

Output Subset SEVSE for all u u WES E S

max DCS Festa

a IF Tsf D8 cost

IIPartition V S UT S selectreduce to min cat problem T throw out

toz

8 Build H

a Tsf Tgf computemaxflowf

return P Ift

f OcuE time

p Emax 63,03 Eo Gmpaff.EE Iobhfepend

profit 5 P lls TH claim

Forany XEV cost Cxotcu cG t

yieldCx Izzo toCu Execs u

profitCx yield X costa IZ u

P yield V yield s yieldCt119TH costs yield TP 115TH yield s cost G profit s U