private static void SubtractTokens(TokenPredictorDatabase accumulator, TokenPredictorDatabase subtractive)
{
var expired = default(List <int>);
foreach (var pair in subtractive)
{
var info = accumulator.GetValue(pair.Key);
if (0 < accumulator.DecrementCount(info, pair.Value.Count))
{
var subtractiveChlidren = pair.Value.TryGetChildren();
if (subtractiveChlidren != null)
{
SubtractTokens(info.GetChildren(), subtractiveChlidren);
}
}
else
{
Debug.Assert(info.Count == 0);
if (expired == null)
{
expired = new List <int>();
}
expired.Add(pair.Key);
}
}
if (expired != null)
{
foreach (var token in expired)
{
accumulator.Remove(token);
}
}
}
private static void AddTokens(TokenPredictorDatabase accumulator, TokenPredictorDatabase additive)
{
foreach (var pair in additive)
{
var info = accumulator.GetValue(pair.Key);
accumulator.IncrementCount(info, pair.Value.Count);
var additiveChlidren = pair.Value.TryGetChildren();
if (additiveChlidren != null)
{
AddTokens(info.GetChildren(), additiveChlidren);
}
}
}
