Int 和字符串在一起

这是我的代码：

 if (numavg <=3 ){
             Console.WriteLine("Congratz, we can start! but some note before :");
             Console.WriteLine("When you put the last number, type 'c' in the next line for calculate the avg");
             Console.WriteLine("So lets start! type the first number.");
             avg1 = int.Parse(Console.ReadLine());
             Console.WriteLine("Ok, so you choose " + avg1 + ",who is the next number?");
             avg2 = int.Parse(Console.ReadLine());
             Console.WriteLine("Wonderful! put the next number");
             avg3 = int.Parse(Console.ReadLine());
             if (avg3 = "c"){
                 Console.WriteLine("Ok, Lets calculate!");
                 average = (avg1 + avg2)/numavg;
                 Console.WriteLine("The average is " + average + ".");

             }
             else {
                 Console.WriteLine("Perfect! please type the next number,or 'c' for avg to the last 3 numbers.");
                 avg4 = int.Parse(Console.ReadLine());

                 if (avg4 = "c" ){
                     Console.WriteLine("Ok, Lets calculate!");
                     average1 = (avg1 + avg2 + avg3)/numavg;
                     Console.WriteLine("The average is " + average1 + ".");

             }
         }

问题出在类型"c"(用于计算平均值(。我不明白如何将 avg3 和 avg4 作为字符串和 int 放在一起。

帮助？

还有更纯粹的问题——如果我希望程序自动结束并重新启动，我需要键入哪个代码？(如果无法重新启动，我该如何关闭自动程序的第一件事？

谢谢你们！

注意：错误是"无法将类型'字符串'隐式转换为'int'"。