33 lines
919 B
C#
33 lines
919 B
C#
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namespace OECS.PlayTest;
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/// <summary>
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/// A pool of agents selected by weight. Higher weight = more likely to be picked.
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/// </summary>
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public class WeightedAgentPool<TDecision>
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{
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private readonly List<(IAgent<TDecision> Agent, int Weight)> _agents = new();
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private int _totalWeight;
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private static readonly Random _rng = new();
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public void Add(IAgent<TDecision> agent, int weight)
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{
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_agents.Add((agent, weight));
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_totalWeight += weight;
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}
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public IAgent<TDecision> Pick()
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{
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if (_agents.Count == 0)
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throw new InvalidOperationException("WeightedAgentPool is empty");
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int roll = _rng.Next(_totalWeight);
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int cumulative = 0;
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foreach (var (agent, weight) in _agents)
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{
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cumulative += weight;
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if (roll < cumulative)
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return agent;
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}
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return _agents[^1].Agent;
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}
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}
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