RosettaCodeData/Task/Binary-search/Picat/binary-search-2.picat
2023-07-01 13:44:08 -04:00

13 lines
496 B
Text

binary_search_rec(A, Value) = Ret =>
Ret = binary_search_rec(A,Value, 1, A.length).
binary_search_rec(A, _Value, _Low, _High) = -1, sort(A) != A => true.
binary_search_rec(_A, _Value, Low, High) = 0, High < Low => true.
binary_search_rec(A, Value, Low, High) = Mid =>
Mid1 = (Low + High) // 2,
if A[Mid1] > Value then
Mid1 := binary_search_rec(A, Value, Low, Mid1-1)
elseif A[Mid1] < Value then
Mid1 := binary_search_rec(A, Value, Mid1+1, High)
end,
Mid = Mid1.