after successful field test Heidi consider deploy trap Corridor possibly she want avoid meet Daleks inside Time Vortex abundance caution consider place trap corridor go accord current Daleks plan use minimum spanning tree Corridors Heidi know energy requirement different Corridors different Daleks single unique plan intend useyour task calculate number e_maxc define way easy version ie large e le 109 change energy corridor c e dalek use corridor Heidi consider