private int GetLastKindAmount(Pair coinsTypes)
{
if (coinsTypes.Next == null)
{
return coinsTypes.Value;
}
return GetLastKindAmount(coinsTypes.Next);
}
private int Calculate(int total, Pair coinsTypes)
{
if (total == 0)
{
return 1;
}
if (total < 0)
{
return 0;
}
if (coinsTypes == null)
{
return 0;
}
return Calculate(total - GetLastKindAmount(coinsTypes), coinsTypes)
+ Calculate(total, Pair.RemoveLast(coinsTypes));
}