foreach (DataRow row in dt.Rows)
{
string name = row["Name"].ToString();
int sumDuration = Convert.ToInt32(row["Duration"]);
if (dicSum.ContainsKey(name))
dicSum[name] += sumDuration;
else
dicSum.Add(name, sumDuration);
}
foreach (string i in dicSum.Keys)
Console.WriteLine("{0}={1}", i, dicSum[i]);
Console.ReadLine();