From 61a4aa2dc2fbf50009d6e6d6e2b2c144e9368d0e Mon Sep 17 00:00:00 2001
From: NanamiAdmin <yzt114@yeah.net>
Date: Thu, 15 Jan 2026 01:24:10 +0800
Subject: [PATCH] Upload files to "/"

---
 linkedList.cpp | 172 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 172 insertions(+)
 create mode 100644 linkedList.cpp

diff --git a/linkedList.cpp b/linkedList.cpp
new file mode 100644
index 0000000..cf086a3
--- /dev/null
+++ b/linkedList.cpp
@@ -0,0 +1,172 @@
+#include <iostream>
+#include <string>
+
+using namespace std;
+
+struct Student {
+    int id;
+    string name;
+    int age;
+    Student* next;
+};
+
+Student* head = nullptr; // Define the head of the linked list
+
+Student* createStudent(int id, const string& name, int age) {
+    Student* s = new Student;
+    s->id = id;
+    s->name = name;
+    s->age = age;
+    s->next = nullptr;
+    return s;
+}
+
+void addStudent(int id, const string& name, int age) { // Add student to the end
+    Student* s = createStudent(id, name, age);
+
+    if (!head) {
+        head = s;
+        return;
+    }
+
+    Student* p = head;
+    while (p->next) {
+        p = p->next;
+    }
+    p->next = s;
+}
+
+Student* findStudent(int id) {
+    Student* p = head;
+    while (p) {
+        if (p->id == id)
+            return p;
+        p = p->next;
+    }
+    return nullptr;
+}
+
+bool updateStudent(int id, const string& newName, int newAge) {
+    Student* s = findStudent(id);
+    if (!s)
+        return false;
+
+    s->name = newName;
+    s->age = newAge;
+    return true;
+}
+
+bool deleteStudent(int id) {
+    if (!head)
+        return false;
+
+    if (head->id == id) { // If head is to be deleted
+        Student* tmp = head;
+        head = head->next;
+        delete tmp;
+        return true;
+    }
+
+    Student* p = head;
+    while (p->next && p->next->id != id) {
+        p = p->next;
+    }
+
+    if (p->next) {
+        Student* tmp = p->next;
+        p->next = tmp->next;
+        delete tmp;
+        return true;
+    }
+
+    return false;
+}
+
+void showStudents() {
+    if (!head) {
+        cout << "No student info.\n";
+        return;
+    }
+
+    Student* p = head;
+    cout << "Student ID\tName\tAge\n";
+    while (p) {
+        cout << p->id << "\t" << p->name << "\t" << p->age << endl;
+        p = p->next;
+    }
+}
+
+void menu() {
+    cout << "\n===== Student Mgmt System =====\n";
+    cout << "1. Add student\n";
+    cout << "2. Delete student\n";
+    cout << "3. Modify student\n";
+    cout << "4. Query student\n";
+    cout << "5. Display all students\n";
+    cout << "0. Exit\n";
+    cout << "Please select£º";
+}
+
+int main() {
+    int choice;
+
+    do {
+        menu();
+        cin >> choice;
+
+        int id, age;
+        string name;
+
+        switch (choice) {
+        case 1:
+            cout << "Student ID - Name - Age£º";
+            cin >> id >> name >> age;
+            addStudent(id, name, age);
+            cout << "Added successfully.\n";
+            break;
+
+        case 2:
+            cout << "Input student ID to delete£º";
+            cin >> id;
+            if (deleteStudent(id))
+                cout << "Deleted.\n";
+            else
+                cout << "Student not found.\n";
+            break;
+
+        case 3:
+            cout << "Enter new Student ID - Name - Age£º";
+            cin >> id >> name >> age;
+            if (updateStudent(id, name, age))
+                cout << "Modified successfully.\n";
+            else
+                cout << "Student not found.\n";
+            break;
+
+        case 4: {
+            cout << "Enter Student ID: ";
+            cin >> id;
+            Student* s = findStudent(id);
+            if (s)
+                cout << "Student ID: " << s->id << " Name: " << s->name << " Age: " << s->age << endl;
+            else
+                cout << "Student not found.\n";
+            break;
+        }
+
+        case 5:
+            showStudents();
+            break;
+
+        case 0:
+            cout << "Exit.\n";
+            break;
+
+        default:
+            cout << "Invalid option.\n";
+        }
+
+    } while (choice != 0);
+
+    return 0;
+}