public InventorySet Negate()
{
var Result = new InventorySet();
foreach (var v in this)
{
Result.Add(v.Key, -v.Value);
}
return(Result);
}
public static InventorySet operator +(InventorySet left, KeyValuePair <string, int> right)
{
var Result = new InventorySet(left);
if (left.ContainsKey(right.Key))
{
Result[right.Key] += right.Value;
}
else
{
Result.Add(right.Key, right.Value);
}
return(Result);
}