Initial data commit

Task/Executable-library/Pascal/executable-library-3.pas

@@ -0,0 +1,43 @@
+{$h+}
+uses
+  SysUtils, DynLibs;
+const
+  LIB_NAME = {$ifdef windows}'exec_lib.exe'{$else}'exec_lib'{$endif};
+type
+  THailSeq   = record
+    Data: PCardinal;
+    Count: Longint;
+  end;
+  THailstone = function(aValue: Cardinal): THailSeq;
+  TCounts    = array[0..511] of Longint;
+var
+  LibName: string;
+  hLib: TLibHandle;
+  Fun: THailstone;
+  I, Len, Count, c: Longint;
+  Counts: TCounts;
+begin
+  LibName := ExtractFilePath(ParamStr(0))+LIB_NAME;
+  hLib := LoadLibrary(LibName);
+  if hLib = NilHandle then begin
+    WriteLn('Can not load library ', LibName); Halt(1);
+  end;
+  Pointer(Fun) := GetProcAddress(hLib, 'Hailstone');
+  if Pointer(Fun) = nil then begin
+    WriteLn('Can not find Hailstone() function'); Halt(2);
+  end;
+  Counts := Default(TCounts);
+  Count := 0;
+  Len := 0;
+  for I := 1 to 100000 do begin
+    c := Fun(I).Count;
+    Inc(Counts[c]);
+    if Counts[c] > Count then begin
+      Count := Counts[c];
+      Len := c;
+    end;
+  end;
+  UnloadLibrary(hLib);
+  WriteLn('The most common Hailstone sequence length in the specified range is ',
+           Len, ', it occurs ', Count, ' times.');
+end.