带权重的随机选择算法 c#
时间: 2024-08-13 21:06:33 浏览: 55
在C#中,带权重的随机选择通常涉及到概率分布和随机数生成。一个常见的方法是使用`System.Collections.Generic.Dictionary<TKey, TValue>`或者`Dictionary<T, double>`来存储元素及其对应的权重,然后利用这些权重来计算每个元素被选中的概率。这里有一个简单的概念实现:
```csharp
using System;
using System.Collections.Generic;
using System.Linq;
class WeightedRandomSelection
{
private readonly Dictionary<int, double> weights;
public WeightedRandomSelection(Dictionary<int, double> weights)
{
this.weights = weights;
// 确保所有权重的和为1(或接近于1),以便进行正确的概率计算
double totalWeight = weights.Values.Sum();
if (totalWeight != 1)
{
weights = weights.ToDictionary(kvp => kvp.Key, kvp => kvp.Value / totalWeight);
}
}
public int Choose()
{
double randomValue = Random.NextDouble(); // 0到1之间的随机浮点数
double cumulativeProbability = 0;
foreach (var (key, weight) in weights)
{
cumulativeProbability += weight;
if (randomValue <= cumulativeProbability)
{
return key;
}
}
throw new InvalidOperationException("无法生成随机选择,可能是因为权重总和不为1");
}
}
public class Program
{
static void Main(string[] args)
{
Dictionary<int, double> selections = new Dictionary<int, double>
{
{1, 0.3},
{2, 0.4},
{3, 0.3}
};
WeightedRandomSelection random = new WeightedRandomSelection(selections);
int chosenNumber = random.Choose();
Console.WriteLine($"随机选择了数字: {chosenNumber}");
}
}
```
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