自定义类：无法比较数组中的两个元素

Question

I have a list of abstract Class elements and when I try to sort it I get an exception with a message "Failed to compare two elements in the array"

Abstract Class:

public abstract class Node : IComparable<Leaf>, IComparable<Interrior>
{
    public virtual ulong Weight { get; set; }
    protected virtual int CompareWeights(Node node)
    {
        if (this.Weight < node.Weight) return -1;
        else if (this.Weight > node.Weight) return 1;
        else return 0;
    }
    public abstract int CompareTo(Interrior node);
    public abstract int CompareTo(Leaf node);
}

Derived classes:

public class Interrior : Node
{
    public Interrior(byte age, Node left, Node right)
    {
        Age = age;
        Left = left;
        Right = right;
        Weight = Left.Weight + Right.Weight;
    }
    public byte Age { get; }
    public Node Left { get; }
    public Node Right { get; }
    public override int CompareTo(Interrior node)
    {
        var result = CompareWeights(node);
        if (result == 0) result = this.Age < node.Age ? -1 : 1;
        return result;
    }
    public override int CompareTo(Leaf node)
    {
        var result = CompareWeights(node);
        if (result == 0) result = 1;
        return result;
    }
}
public class Leaf : Node
{
    public Leaf(byte symbol)
    {
        Symbol = symbol;
        Weight = 1;
    }
    public byte Symbol { get; }
    public override int CompareTo(Interrior node)
    {
        var result = CompareWeights(node);
        if (result == 0) result = -1;
        return result;
    }

    public override int CompareTo(Leaf node)
    {
        var result = CompareWeights(node);
        if (result == 0) result = this.Symbol < node.Symbol ? -1 : 1;
        return result;
    }
}

Can anybody please tell me what I'm doing wrong here? I want to create List of nodes and call a method sort on it, thank you.

Answer 1

You don't have an IComparable<Node> on the base. Implement that, and delegate it to the ones you implemented for Interior and Leaf.