Add lang file, ...

LTWindows.sln

@@ -3,7 +3,7 @@ Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio Version 17
 VisualStudioVersion = 17.4.33110.190
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "LTWindows", "LTWindows\LTWindows.csproj", "{082D1086-846A-4D1E-8DBC-08BA8DAD2B99}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "LTWindows", "LTWindows\LTWindows.csproj", "{082D1086-846A-4D1E-8DBC-08BA8DAD2B99}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -20,6 +20,7 @@ Global
 		HideSolutionNode = FALSE
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
+		RESX_NeutralResourcesLanguage = vi-VN
 		SolutionGuid = {46D3B702-0E82-438F-AE3A-FF2A3E34584B}
 	EndGlobalSection
 EndGlobal

LTWindows/Core/Matrix.cs

@@ -77,7 +77,7 @@ public static Matrix Plus(Matrix a, Matrix b)
 			if (a.SoCot != b.SoCot || a.SoDong != b.SoDong)
 			{
 				MessageBox.Show("Không tính được!");
-                return null;
+				return null;
 			}
 
 			Matrix result = new(a.SoCot, a.SoDong);
@@ -93,5 +93,21 @@ public static Matrix Plus(Matrix a, Matrix b)
 			return result;
 		}
 
+
+		public static bool isUpperTriangular(Matrix a)
+		{
+			if (!a.isSquare) return false;
+
+			for (int i = 0; i < a.SoDong; i++)
+			{
+				for (int j = i + 1; j < a.SoCot; j++)
+				{
+					if (a.matrix[i, j] != 0) return false;
+				}
+			}
+
+			return true;
+		}
+
 	}
 }

LTWindows/LTWindows.csproj

@@ -14,13 +14,23 @@
       <AutoGen>True</AutoGen>
       <DependentUpon>Resources.resx</DependentUpon>
     </Compile>
+    <Compile Update="Resources\Lang\Resource.Designer.cs">
+      <DesignTime>True</DesignTime>
+      <AutoGen>True</AutoGen>
+      <DependentUpon>Resource.resx</DependentUpon>
+    </Compile>
   </ItemGroup>
 
   <ItemGroup>
     <EmbeddedResource Update="Properties\Resources.resx">
       <Generator>ResXFileCodeGenerator</Generator>
       <LastGenOutput>Resources.Designer.cs</LastGenOutput>
     </EmbeddedResource>
+    <EmbeddedResource Update="Resources\Lang\Resource.resx">
+      <Generator>PublicResXFileCodeGenerator</Generator>
+      <LastGenOutput>Resource.Designer.cs</LastGenOutput>
+      <CustomToolNamespace>LTWindows.Language</CustomToolNamespace>
+    </EmbeddedResource>
   </ItemGroup>
 
 </Project>