Citation
Abstract
pritlrity queue (pQ) on n wires. In IIIC example of Fig, I wc could Il:lndlc crnc more user of higher priorily thwr Ihv o[hcrs. ;Illowing hinl just OHC button. TIIC schcmc in Fig. 3 shows u w:ty of putting II users on n wires, giving two buttons cuch IO :111Ihc hwcr priority users and one button to the top priority user. A chwrly dcllnctl combimrtorial problcm arises frwn !Iw cx:tmplc SCIICIVCof Fig. 3. LMcr IIIC gi\vn conditions. could :Iny of IIIC users be given more buttons’? Arthur tlubin IKIS givclt a proof tkrt tlIc wsswer is “no.” TluIs IIIC optinurlily of IhcSCIICINC in Fig. 3 hasbeen provctl, IIcrc is proof (due to Lloyd \VclclI) Ikrt if tl]crc orc n users, tllcn there nlust he al Icost n wires. ml Ihc lop priority user c:In be given only one button. \Vc ussumc. of course, Ilutt each user lurs at Icmt one but. ton, ;md s:ly that lhc users are I.2. 000, n with II having top priority. Consith?r the following Scqucnct of possibilities. (1) User I (lowcsI priority) pushes onc of his buttons. For tcnlr:tl t(l know it there must be at Icust one wire Icl”s C311il pi. (2) User I is {w p, und user 2 pushes onc of user 2’s btIIImIs. Tllcrc must bc another \\’ire p: jtls[ to tell tluII (Iliglwr priorily) ustr 2 is dcm:mcling sonwllling. (,1) User 1 is on p,. user 2 is on p,. 000, user n-l is on /),,,, . ond user H pushes onc of II;S buttons. t\s in t:wh previous C:ISC. Ihcrc mIISI be :moth’r wire p,, different “. Iron) llw wires p,. ”‘ 0. pn,l just IV.. Conclusion uwr 11isdcnxlnding something. Fin:llly. Ihc top priority user scclmd hlllton Iwc:lllsc 111:11Wollld wire difftrcnl from p,, . . 0, /),,. , /1,, . Ill. Application
Details
- Volume
- 42-51
- Published
- June 15, 1979
- Pages
- 141–143
- File Size
- 157.2 KB