读取多个记录以计算点之间的最短距离时出错

Question

我试图编写这个伪代码，但结果不正确。 这是伪代码：

total_distance = distance(student(1), school)
For i = 1 to m-1 do (m is the number of students in the cluster)
    Total_distance = total_distance + distance(student(i), student(i+1))
End for

这是我的代码：

Answer 1

据我所知，你试着读两次学生的坐标： 首先，当你找到它与之前学生之间的距离时，第二，当你在tempLong和tempLat中保存它的坐标时。我猜你的输入不包含每个学生两次。 为避免两次读取每个值，您可以存储以前的值，如下所示：

    double curLong = 0.0;
    double curLat = 0.0;
    double prevLong = (double)schoolLocLon;
    double prevLat = (double)schoolLocLat;
    double totalDistance = 0.0;
    while (readStd.Read())
    {
        curLong = Convert.ToDouble(readStd.GetValue(0));
        curLat = Convert.ToDouble(readStd.GetValue(1));
        totalDistance += DistanceBetweenPlaces(prevLong, prevLat, curLong, curLat);
        prevLong = curLong;
        prevLat = curLat;
    }