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with Interfaces; use Interfaces;
package body Natools.Static_Maps.S_Expressions.Conditionals.Strings.P is
P : constant array (0 .. 2) of Natural :=
(2, 11, 13);
(1, 11, 13);
T1 : constant array (0 .. 2) of Unsigned_8 :=
(9, 9, 0);
(11, 3, 3);
T2 : constant array (0 .. 2) of Unsigned_8 :=
(6, 4, 5);
(14, 19, 16);
G : constant array (0 .. 16) of Unsigned_8 :=
(0, 5, 0, 1, 0, 6, 0, 0, 7, 0, 0, 0, 0, 1, 1, 0, 3);
G : constant array (0 .. 22) of Unsigned_8 :=
(0, 0, 0, 9, 0, 0, 0, 0, 2, 0, 3, 0, 0, 3, 1, 0, 7, 0, 4, 0, 1, 7, 0);
function Hash (S : String) return Natural is
F : constant Natural := S'First - 1;
L : constant Natural := S'Length;
F1, F2 : Natural := 0;
J : Natural;
begin
for K in P'Range loop
exit when L < P (K);
J := Character'Pos (S (P (K) + F));
F1 := (F1 + Natural (T1 (K)) * J) mod 17;
F2 := (F2 + Natural (T2 (K)) * J) mod 17;
F1 := (F1 + Natural (T1 (K)) * J) mod 23;
F2 := (F2 + Natural (T2 (K)) * J) mod 23;
end loop;
return (Natural (G (F1)) + Natural (G (F2))) mod 8;
return (Natural (G (F1)) + Natural (G (F2))) mod 11;
end Hash;
end Natools.Static_Maps.S_Expressions.Conditionals.Strings.P;
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