Data update

Task/Left-factorials/Ada/left-factorials.ada

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+-- Rosetta Code Task written in Ada
+-- Left factorials
+-- https://rosettacode.org/wiki/Left_factorials
+-- (Mostly) translated from the AWK example
+-- February 2025, R. B. E.
+-- Using PragmARC.Unbounded_Numbers, GNAT version 14.2.0-3, MacOS 15.3, M1 chip
+
+with Ada.Text_IO; use Ada.Text_IO;
+with Ada.Integer_Text_IO; use Ada.Integer_Text_IO;
+with PragmARC.Unbounded_Numbers.Integers; use PragmARC.Unbounded_Numbers.Integers;
+
+procedure Left_Factorials is
+
+  function Left_Fact (F : Natural) return Unbounded_Integer is
+    Result : Unbounded_Integer := To_Unbounded_Integer (0);
+    Adder : Unbounded_Integer := To_Unbounded_Integer (1);
+  begin
+    if F = 0 then
+      return Result;
+    end if;
+    for K in 1..F loop
+      Result := Result + Adder;
+      Adder := Adder * To_Unbounded_Integer (K);
+    end loop;
+    return Result;
+  end Left_Fact;
+
+  function Brute_Force_Digit_String_Length (N : in Unbounded_Integer) return Natural is
+    Big_Zero : constant Unbounded_Integer := To_Unbounded_Integer (0);
+    Big_Ten : constant Unbounded_Integer := To_Unbounded_Integer (10);
+    Local_N : Unbounded_Integer := N;
+    String_Length : Natural := 0;
+  begin
+    loop
+      exit when Local_N = Big_Zero;
+      Local_N := Local_N / Big_Ten;
+      String_Length := String_Length + 1;
+    end loop;
+    return String_Length;
+  end Brute_Force_Digit_String_Length;
+
+begin
+  for I in 0..10 loop
+    Put ("!");
+    Put (I, 0);
+    Put (" = ");
+    Put (Image (Value => Left_Fact (I)));
+    New_Line;
+  end loop;
+  New_Line;
+  for I in 20..110 loop
+    if (I mod 10) = 0 then
+      Put ("!");
+      Put (I, 0);
+      Put (" =");
+      if I < 70 then
+        Put (" ");
+      else
+        New_Line;
+      end if;
+      Put (Image (Value => Left_Fact (I)));
+      New_Line;
+    end if;
+  end loop;
+  New_Line;
+  for I in 1_000..10_000 loop
+    if (I mod 1_000) = 0 then
+      Put ("!");
+      Put (I, 0);
+      Put (" has ");
+      Put (Brute_Force_Digit_String_Length (Left_Fact (I)), 0);
+      Put_Line (" digits.");
+    end if;
+  end loop;
+  New_Line;
+end Left_Factorials;