Csharp 根据优先级整理合同列表

我有一个合同 list ，这些合同都有完成的时间跨度.有些合同比其他合同更重要.如果两个合约之间有重叠，我们就会将不太重要的合约砍成两半，从头开始或从尾砍掉，或者完全取消.

My problem is: I've implemented the algorithm but I still have some minor errors which cause a false output.
e.g.

Input:
Start     Ende        Preis  Priorität
1.1.2020  1.3.2020    20,40  1
1.2.2020  31.12.2020  18,00  2
1.6.2020  1.9.2020    16,90  3

Output should be:
Start     Ende        Preis
1.1.2020  31.1.2020   20,40
1.2.2020  31.5.2020   18,00
1.6.2020  1.9.2020    16,90
2.9.2020  31.12.2020  18,00

我的代码:

List<Contract> contractList = //get value based on a file and get sorted based on the priority;
List<Contract> resultContracts = new List<Contract>()
{
    contractList[0]
};
int n = contractList.Count;
for (var i = 0; i < contractList.Count; i++)
{

    var lastProcessedContract = contractList[i]; // high priority
    var contractsToRemove = new List<Contract>();
    var contractsToAdd = new List<Contract>();
    for (var j = i + 1;  j < contractList.Count; j++){

        var lessPriorityContract = contractList[j];
        if (contractList[j].priority == contractList[i].priority)
        {
            continue;
        }
        if (lessPriorityContract.start >= lastProcessedContract.start && lessPriorityContract.end <= lastProcessedContract.end)
        /*
         *  ------------------------>
         *           ------>
         * oder
         *  ------------------------>
         *  -------->
         * oder
         *  ------------------------->
         *                    ------->
         * oder
         * --------------------------->
         * --------------------------->
         */
        {
            contractsToRemove.Add(lessPriorityContract);
        }
        else if ((lessPriorityContract.start < lastProcessedContract.start 
                 && (lessPriorityContract.end > lastProcessedContract.start && lessPriorityContract.end <= lastProcessedContract.end)) || 
                 ((lastProcessedContract.start < lessPriorityContract.end && lastProcessedContract.start > lessPriorityContract.start)
                     && lastProcessedContract.end > lessPriorityContract.end))
       /* 
          *     ------------------------>
          *  ------>
          * oder
          *     ------------------------------->
          * ----------------------------------->

        // oder

          *                   -------------->
          *  ------------------------>
        */

        {
            lessPriorityContract.end = lastProcessedContract.start.AddDays(-1);
            resultContracts.Add(lessPriorityContract);
        }
        else if (((lessPriorityContract.start < lastProcessedContract.end && lessPriorityContract.start >= lastProcessedContract.start)
                 && lessPriorityContract.end > lastProcessedContract.end) || (lastProcessedContract.start < lessPriorityContract.start &&
                                                                              (lastProcessedContract.end > lessPriorityContract.start && lastProcessedContract.end < lessPriorityContract.end)))
        /*
         * -------------------->
         *            ------------------------->
         * oder
         * -------------------->
         * ---------------------------------->
         *

        //oder

          *  ------------>
          *       ------------------->
          * 
         */ 
        {
            lessPriorityContract.start = lastProcessedContract.end.AddDays(1);
            resultContracts.Add(lessPriorityContract);
        }
        else if(lessPriorityContract.start < lastProcessedContract.start
                && lessPriorityContract.end > lastProcessedContract.end)
            /*
             *       ------------>
             * --------------------------->
             * oder
             * --------------------------->
             * --------------------------->
             * 
             */
        {
            contractsToRemove.Add(lessPriorityContract);
            var contract = new Contract
            {
                start = lessPriorityContract.start,
                end = lastProcessedContract.start.AddDays(-1),
                priority = lessPriorityContract.priority,
                price = lessPriorityContract.price
            };
            contractsToAdd.Add(contract);

            //contractList.Remove(contractList[i]);
            //contractList.Add(contract);
            resultContracts.Add(contract);
            contract = new Contract
            {
                start = lastProcessedContract.end.AddDays(1),
                end = lessPriorityContract.end,
                priority = lessPriorityContract.priority,
                price = lessPriorityContract.price
            };
            resultContracts.Add(contract);
            contractsToAdd.Add(contract);

            //contractList.Add(contract);
        }
        else
        {
            resultContracts.Add(lessPriorityContract);
        }
    }
    foreach (var contractToRemove in contractsToRemove)
    {
        contractList.Remove(contractToRemove);
        resultContracts.Remove(contractToRemove);
    }

    foreach (var contractToAdd in contractsToAdd)
    {
        contractList.Add(contractToAdd);
    }
    contractList.Sort();
}

resultContracts.Sort(new ContractComparer()); // Sorting based on start time of the contract
resultContracts = resultContracts.Distinct().ToList();
foreach (var flatElement in resultContracts)
{
    Console.WriteLine(flatElement.ToString());
    Console.WriteLine();
}

resultContracts.Sort();
Console.WriteLine("-------------------------------");
foreach (var flatElement in resultContracts)
{
    Console.WriteLine(flatElement.ToString());
    Console.WriteLine();
}

Class协定具有属性(开始、结束、价格、优先级)和一个从Icomparable开始的重写方法，以帮助根据优先级进行排序.

我对获得新的高效和更快的算法也持开放态度，否则修复这个也会很有帮助.

编辑:小通知是，我现在并不关心我输出了多少属性，只要我解决了算法，我就可以处理这些:)