2023-10-19

2023-10-19 11:48:05 +08:00
commit 121d4a1c90
56 changed files with 2958 additions and 0 deletions
--- a/Classwork2/Classwork2.sln
+++ b/Classwork2/Classwork2.sln
@@ -0,0 +1,71 @@
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--- a/Classwork2/S2_1/S2_1.cpp
+++ b/Classwork2/S2_1/S2_1.cpp
@@ -0,0 +1,16 @@
+#include <iostream>
+using namespace std;
+int main()
+{
+	float a, b, c;
+	cout << "input a b c\n";
+	cin >> a >> b >> c;
+	if ((a + b <= c) || (a + c <= b) || (b + c <= a))
+		cout << "Not Triangle\n";
+	else
+		cout << "Triangle\n";
+	return 0;
+}
+
+// 3 4 5 -> Triangle
+// 1 2 5 -> Not Triangle
--- a/Classwork2/S2_1/S2_1.vcxproj
+++ b/Classwork2/S2_1/S2_1.vcxproj
@@ -0,0 +1,135 @@
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+++ b/Classwork2/S2_1/S2_1.vcxproj.filters
@@ -0,0 +1,22 @@
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--- a/Classwork2/S2_2/S2_2.cpp
+++ b/Classwork2/S2_2/S2_2.cpp
@@ -0,0 +1,16 @@
+#include <iostream>
+using namespace std;
+int main()
+{
+	int year;
+	cout << "Input year: ";
+	cin >> year;
+	if (year % 400 == 0 || (year % 4 == 0 && year % 100 != 0))
+		cout << year << " is a leap year" << endl;
+	else
+		cout << year << " isn\'t a leap year" << endl;
+	return 0;
+}
+
+// 2000 -> 2000 is a leap year
+// 2200 -> 2200 isn't a leap year
--- a/Classwork2/S2_2/S2_2.vcxproj
+++ b/Classwork2/S2_2/S2_2.vcxproj
@@ -0,0 +1,135 @@
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--- a/Classwork2/S2_3/S2_3.cpp
+++ b/Classwork2/S2_3/S2_3.cpp
@@ -0,0 +1,33 @@
+#include <iostream>
+using namespace std;
+int main()
+{
+	float a1, a2;
+	char oper;
+	float result;
+	int flag = 0;
+	cout << "请输入简单的运算式：\n";
+	cin >> a1 >> oper >> a2;
+	switch (oper)
+	{
+	case '+':
+		result = a1 + a2;
+		break;
+	case '-':
+		result = a1 - a2;
+		break;
+	case '*':
+		result = a1 * a2;
+		break;
+	default:
+		cout << "输入错误的运算符!\n";
+		flag = 1;
+	}
+	if (flag == 0)
+		cout << a1 << oper << a2 << " = " << result << endl;
+	return 0;
+}
+
+// 4.5+7.2 -> 4.5+7.2 = 11.7
+// 4*5 -> 4*5 = 20
+// 8/2 -> 输入错误的运算符!
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--- a/Classwork2/S2_4/S2_4.cpp
+++ b/Classwork2/S2_4/S2_4.cpp
@@ -0,0 +1,18 @@
+#include <iostream>
+#include <cmath>
+using namespace std;
+int main()
+{
+	int a, b, c;
+	cin >> a >> b >> c;
+	int delta = b * b - 4 * a * c;
+	if (delta < 0)
+		cout << "无实根！" << endl;
+	else
+	{
+		double x1 = (-b + sqrt(delta)) / (2 * a);
+		double x2 = (-b - sqrt(delta)) / (2 * a);
+		cout << x1 << '\t' << x2 << endl;
+	}
+	return 0;
+}
--- a/Classwork2/S2_4/S2_4.vcxproj
+++ b/Classwork2/S2_4/S2_4.vcxproj
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--- a/Classwork2/S2_5/S2_5.cpp
+++ b/Classwork2/S2_5/S2_5.cpp
@@ -0,0 +1,41 @@
+#include <iostream>
+using namespace std;
+int main()
+{
+	float a1, a2;
+	char oper;
+	float result;
+	int flag = 0;
+	cout << "请输入简单的运算式：\n";
+	cin >> a1 >> oper >> a2;
+	switch (oper)
+	{
+	case '+':
+		result = a1 + a2;
+		break;
+	case '-':
+		result = a1 - a2;
+		break;
+	case '*':
+		result = a1 * a2;
+		break;
+	case '/':
+		if (a2 == 0)
+		{
+			cout << "除数不可为0!\n";
+			flag = 1;
+			break;
+		}
+		else
+		{
+			result = a1 / a2;
+			break;
+		}
+	default:
+		cout << "输入错误的运算符!\n";
+		flag = 1;
+	}
+	if (flag == 0)
+		cout << a1 << oper << a2 << " = " << result << endl;
+	return 0;
+}
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+    <ClCompile Include="S2_5.cpp" />
+  </ItemGroup>
+  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
+  <ImportGroup Label="ExtensionTargets">
+  </ImportGroup>
+</Project>
--- a/Classwork2/S2_5/S2_5.vcxproj.filters
+++ b/Classwork2/S2_5/S2_5.vcxproj.filters
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <ItemGroup>
+    <Filter Include="源文件">
+      <UniqueIdentifier>{4FC737F1-C7A5-4376-A066-2A32D752A2FF}</UniqueIdentifier>
+      <Extensions>cpp;c;cc;cxx;c++;cppm;ixx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
+    </Filter>
+    <Filter Include="头文件">
+      <UniqueIdentifier>{93995380-89BD-4b04-88EB-625FBE52EBFB}</UniqueIdentifier>
+      <Extensions>h;hh;hpp;hxx;h++;hm;inl;inc;ipp;xsd</Extensions>
+    </Filter>
+    <Filter Include="资源文件">
+      <UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
+      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
+    </Filter>
+  </ItemGroup>
+  <ItemGroup>
+    <ClCompile Include="S2_5.cpp">
+      <Filter>源文件</Filter>
+    </ClCompile>
+  </ItemGroup>
+</Project>
--- a/Classwork2/实验报告.doc
+++ b/Classwork2/实验报告.doc