-up b-p b-u bbb bbp bbr bbs bbu bpb bpp bpr bps bpu brb brp brr brs bru bsb bsp bsr bss bsu bub bup bur bus buu p-p pbb pbp pbr pbs pbu ppb ppp ppr pps ppu prb prp prr prs pru ps- psb psp psr pss psu pub pup pur pus puu rbb rbp rbr rbs rbu rpb rpp rpr rps rpu rrb rrp rrr rrs rru rsb rsp rsr rss rsu rub rup rur rus ruu sbb sbp sbr sbs sbu spb spp spr sps spu sr- srb srp srr srs ss- ssb ssp ssr sss ssu sub sup sur sus suu ubb ubp ubr ubs ubu up- upb upp upr ups upu ur- urb urp urr urs uru usb usp usr uss usu uur uus uuu

bbbb bbbs bbpr bpsu brrr brrs brsb brsr brup brus bspp bspr bsup bubb bubs bubu bups bur- burb burp burr burs buru buss busu buus pbrs pbsp pppp ppps ppru ppss ppur prbs prps prrs prss prus pruu psbr pspp pspr psps psrp pubs pubu pups pupu pur- purb purp purr purs puru puss rbbb rbbr rbbs rbsp rbss rpps rrrr rrsp rspb rsps rubb rubp rubs rubu rupp rurp rurs ruru russ rusu sbbs sbsp sbus spps sprs spsp spss spur spus srps srsp srub ssbr ssps ssrs sssb ssss sub- subb subs sup- supp supr sups sur- surp surr surs suru sus- susp suss susu suus u-rp uppp uppu upup urbs urss ursu urup urur urus usbr usbs uspp usps ussb ussr usss ussu usus uuuu

bbuss brrrr bruss burbs burps burrs burru burus bussu busur busuu pruss purrs purus puurs rrsps rubup rubus s-bus spurr spurs srprb sssrb sssss subbu subss supps supur surpu surur surus susus ursus urubu usurp uuuuu

bbbbbb brubru bububu burbur burrup pppppp ppsspp pubsub purpur rub-up russus srprss suburb susurr ubussu uruppu usurps

bbbbbbb burruss sssssss suburbs

bbbbbbbb buruburu sussurus susurrus

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