have hb : (f.assignments, ([] : List (Literal (PosFin n))), false, false).1.size = f.assignments.size := rfl
n : Nat
f : DefaultFormula n
rupHints : Array Nat
⊢ (List.foldl (confirmRupHint f.clauses) (f.assignments, [], false, false) rupHints.data).fst.size = f.assignments.size
n : Nat
f : DefaultFormula n
rupHints : Array Nat
hb : (f.assignments, [], false, false).fst.size = f.assignments.size
⊢ (List.foldl (confirmRupHint f.clauses) (f.assignments, [], false, false) rupHints.data).fst.size = f.assignments.size