fix

Author: linzhijun

csharp/ToolGood.Algorithm/Internals/MathSplitVisitor2.cs

@@ -1,10 +1,7 @@
 using Antlr4.Runtime;
 using Antlr4.Runtime.Tree;
-using System;
 using System.Collections.Generic;
-using System.Text;
 using ToolGood.Algorithm.Enums;
-using ToolGood.Algorithm.Internals.Functions;
 using ToolGood.Algorithm.math;
 
 namespace ToolGood.Algorithm.Internals