Sum finder

sumfinder.pi

import planner.

main =>
    S0 = {22, 0, [6, 6, 9, 5, 9, 1, 10, 9, 9, 3]},
    plan(S0, Plan),
    nl,
    writeln(Plan),
    nl.

final({Target, Current, _}) => 
  Target = Current.

action(S0, S1, Action, ActionCost) =>
   Action = {add, X, Next},
   ActionCost = 1,
   S0 = {Target, Current, L},
   member(X, L),
   Next = Current + X,
   not member(Next, [12, 21]),
   S1 = {Target, Next, delete(L, X)},
   true.