189 (fixed point) Let L be a nonempty sorted list of different integers. Write a program to findafixed-pointof L,thatisanindex i suchthat Li=i,ortoreportthatnosuch index exists. Execution time should be at most log (#L) .
§ Let L be a constant, and let i and j be a natural variables. Let t be an extended natural time variable. If a fixed-point exists, it will be indicated by Liʹ=iʹ . If none exists, that will be indicated by Liʹ⧧iʹ .
(∃k: 0,..#L· Lk=k) = (Liʹ=iʹ) ⇐ i:= 0. j:= #L. i