/// <summary>
/// 如果已经收到了某个片断，则首先采用最小优先选择策略，然后才采用严格优先选择策略
/// </summary>
/// <param name="haveFunction">判断是否已经选择函数</param>
/// <returns>返回选择片断的索引号</returns>
private int GotAnySelect(WantDelegate haveFunction)
{
//如果所有的收到have信息数量最小为1的片断都已经被选择，则返回-1
//所以best初始化为-1
int best = -1;
//保存最小的have信息数量
int bestNumber = int.MaxValue;
//严格优先选择策略
foreach (int index in started)
{
if (haveFunction(index) && interestsNumber[index] < bestNumber)
{
best = index;
bestNumber = interestsNumber[index];
}
}
//如果bestNumber > interests的数量，则bestNumber = interests.Count
if (bestNumber > interests.Count)
{
bestNumber = interests.Count;
}
//最小优先选择策略
List <int> randomPieces, interestPieces;
for (int i = 1; i < bestNumber; i++)
{
randomPieces = interests[i];
interestPieces = new List <int>(randomPieces);
randomPieces.Clear();
//随机选择策略
while (interestPieces.Count > 0)
{
int k = ran.Next(interestPieces.Count);
randomPieces.Add(interestPieces[k]);
interestPieces.RemoveAt(k);
}
foreach (int index in randomPieces)
{
//如果未被选择，则返回选择的片断索引号
if (haveFunction(index))
{
return(index);
}
}
}
//如果不能够采用最小优先选择策略，则采用严格优先选择策略
return(best);
}
/// <summary>
/// 计算下一个被选择的片断
/// </summary>
/// <param name="haveFunction">判断是否已经选择函数</param>
/// <returns>返回选择片断的索引号</returns>
public int Next(WantDelegate haveFunction)
{
if (gotAny)
{
return(GotAnySelect(haveFunction));
}
else
{
return(GotNothingSelect(haveFunction));
}
}
/// <summary>
/// 如果没有收到了任何片断，则首先采用严格优先选择策略，然后才采用最小优先选择策略
/// </summary>
/// <param name="haveFunction">判断是否已经选择函数</param>
/// <returns>返回选择片断的索引号</returns>
private int GotNothingSelect(WantDelegate haveFunction)
{
int number;
//严格优先选择策略
foreach (int index in started)
{
//如果未被选择，则返回选择的片断索引号
if (haveFunction(index))
{
return(index);
}
}
List <int> leastPieces = new List <int>();
//最小优先选择策略，但是要保证收到的have信息最小为1
for (number = 1; number < interests.Count; number++)
{
leastPieces.AddRange(interests[number]);
}
//排除已经选择的片断索引号
leastPieces.Except(started);
//用于保存随机选择的结果
List <int> randomPieces = new List <int>();
//随机选择策略
while (leastPieces.Count > 0)
{
int k = ran.Next(leastPieces.Count);
randomPieces.Add(leastPieces[k]);
leastPieces.RemoveAt(k);
}
foreach (int index in randomPieces)
{
//如果未被选择，则返回选择的片断索引号
if (haveFunction(index))
{
return(index);
}
}
//如果所有的收到have信息数量最小为1的片断都已经被选择，则返回-1
return(-1);
}
public int Next(WantDelegate haveFunction)
{
return(0);
}
