继承计算器
..........\Calculator
..........\Calculator.sln
..........\Calculator.suo
..........\..........\bin
..........\..........\...\Debug
..........\..........\...\.....\Calculator.exe
..........\..........\...\.....\Calculator.pdb
..........\..........\...\.....\Calculator.vshost.exe
..........\..........\...\.....\Calculator.vshost.exe.manifest
..........\..........\Calculator.csproj
..........\..........\obj
..........\..........\...\Debug
..........\..........\...\.....\Calculator.csproj.FileListAbsolute.txt
..........\..........\...\.....\Calculator.exe
..........\..........\...\.....\Calculator.pdb
..........\..........\...\.....\Refactor
..........\..........\...\.....\TempPE
..........\..........\Operation.cs
..........\..........\OperationAdd.cs
..........\..........\OperationDiv.cs
..........\..........\OperationMul.cs
..........\..........\OperationSub.cs
..........\..........\Program.cs
..........\..........\Properties
..........\..........\..........\AssemblyInfo.cs