Trace the closest helicopter to the base station

heli_link_dis(h1,b1,800).   
heli_link_dis(h1,b3,1400).  
heli_link_dis(h1,b2,600).  
heli_link_dis(h1,b8,1200). 开发者_StackOverflow社区 
heli_link_dis(h2,b4,400).  
heli_link_dis(h2,b3,2000).  
heli_link_dis(h2,b5,500).  
heli_link_dis(h3,b5,1000).  
heli_link_dis(h3,b6,400).  

heli_link_dis = helicopter linked distance

h1 mean the name of a helicopter

b1 means the name of a base station

800 is the distance between helicopter and the base station

I need the prolog code to trace the closest helicopter to a given base station

An extremely inefficient, yet minimalist, solution is:

nearest_heli(H, B, D) :-
  heli_link_dis(H, B, D),
  \+ (heli_link_dis(_, _, D1), D1 < D).