计算同一时期发生的时间的算法

Question

我已经针对这个问题制定了一个算法，但它仍然遇到了麻烦。

假设我有一个时间表的回顾（包含在名为GV的gridview上）：

TimeStart  TimeEnd   TotalOccuredOnThisTime
----------------------------------------------
08.00      08.50     1
08.00      09.40     43
08.00      10.50     2

请查看下面的图片以获取更清晰的信息：

我想从算法得到的是计算同一时期发生的时间，例如在08.00的时间，它发生了46事件（见黄色行）。

这是我的算法：

Dim ColumnLength As Integer = GV.Rows.Count
Dim TimeStart(ColumnLength - 1) As Integer
Dim TimeEnd(ColumnLength - 1) As Integer
Dim Total(ColumnLength - 1) As Integer

For i = 0 to ColumnLength - 1
  TimeStart(i) = Convert.ToInt32(Regex.Replace(GV.Rows(i).Cells(0).Text, ".", ""))
  TimeEnd(i) = Convert.ToInt32(Regex.Replace(GV.Rows(i).Cells(1).Text, ".", ""))
  Total(i) = 0
Next 

For i = 0 To ColumnLength - 2
  For j = 0 To ColumnLength - 1        
    If TimeEnd(i) > TimeStart(j) And ((TimeStart(i) <= TimeEnd(j)) Or (TimeStart(i) >= TimeEnd(j))) 
      Total(j) = Total(j) - Total(i)
    End If
  Next
Next

但这导致错误的价值。

我想要的结果是：

Time: 08.00 - 08.50   --> 46 event occured
      08.50 - 09.40   --> 46 event occured
      09.40 - 10.00   --> 45 event occured
      etc...

如何正确地做到这一点？真的需要你的帮助......

Answer 1

您可以使用Dictionary通过将Key的两个时间字符串连接在一起来跟踪时间范围（不需要转换为整数），然后对于该范围的每次出现您可以增加Value的{​​{1}}部分。

此外，不需要使用此方法嵌套循环，也不需要使用分段循环来填充开始和结束时间数组。以下算法应提供您要查找的结果：

Dictionary

因此，您可以通过以下方式从字典中提取时间范围09.40 - 10.00的计数：

Dim columnLength As Integer = GV.Rows.Count
Dim timeRangeCount As New Dictionary(Of String, Integer)

For i = 0 to columnLength - 1
  Dim timeStart As String = GV.Rows(i).Cells(0).Text
  Dim timeEnd As String = GV.Rows(i).Cells(1).Text
  Dim key As String = String.Format("{0}-{1}", timeStart, timeEnd)

  If timeRangeCount.ContainsKey(key)
      timeRangeCount(key) += 1
  Else
      timeRangeCount(key) = 1
  End If
Next

---

我已使用类似的测试代码验证此算法：

Dim totalOccuredOnThisTime As Integer = timeRangeCount("09.40-10.00")

更新

在您的评论中阅读了您的说明后，您仍然可以使用词典来帮助跟踪这一点以及几个辅助类（Dim columnLength As Integer = 6 Dim timeStart() As String = {"08.00", "08.00", "10.00", "08.00", "08.00", "10.00"} Dim timeEnd() As String = {"08.50", "08.50", "11.00", "09.00", "08.50", "11.00"} Dim timeRangeCount As New Dictionary(Of String, Integer) For i = 0 to columnLength - 1 Dim key As String = String.Format("{0}-{1}", timeStart(i), timeEnd(i)) If timeRangeCount.ContainsKey(key) timeRangeCount(key) += 1 Else timeRangeCount(key) = 1 End If Next Console.WriteLine(timeRangeCount) ，TimeRange和TimeRangeCounter）。这确实使事情变得复杂一些。

第一个辅助类用于保存精确匹配和子范围匹配的计数：

TimeRangeEqualityComparer

第二个辅助类用于帮助字典知道一个密钥（类型Public Class TimeRangeCounter Property ExactRangeMatch as Integer Property SubRangeMatch as Integer End Class ）与另一个密钥的区别：

TimeRange

第三个助手类存储范围的开始和结束时间：

Public Class TimeRangeEqualityComparer 
    Implements IEqualityComparer(Of TimeRange)

    Public Overloads Function Equals(left As TimeRange, right As TimeRange) _
            As Boolean Implements IEqualityComparer(Of TimeRange).Equals           

        Return left.ToString = right.ToString   
    End Function

    Public Overloads Function GetHashCode(range As TimeRange) _
            As Integer Implements IEqualityComparer(Of TimeRange).GetHashCode

        return range.ToString().GetHashCode()
    End Function

End Class

所以使用上面我们应该能够编写这个算法：

Public Class TimeRange 
    Private readonly _start
    Private readonly _end

    Public Readonly Property Start 
        Get
           return _start
        End Get
    End Property

    Public Readonly Property [End] 
        Get
           return _end
        End Get
    End Property

    Public Sub New(start As String, [end] As string)
        Me._start = start
        Me._end = [end]
    End Sub

    Public Overrides Function ToString() as String
       Return String.Format("{0}-{1}", Start, [End])
    End Function

End Class