diff --git a/undergraduateManager.h b/undergraduateManager.h
new file mode 100644
index 0000000..bf779ad
--- /dev/null
+++ b/undergraduateManager.h
@@ -0,0 +1,169 @@
+#pragma once
+#ifndef UNDERGRADUATE_MANAGER_H
+#define UNDERGRADUATE_MANAGER_H
+#include <iostream>
+#include <string>
+#include <fstream>
+#include "undergraduate.h"
+using namespace std;
+class UnderGraduateManager {
+private:
+	int top = 0;
+	UnderGraduate undergraduates[100];
+public:
+	UnderGraduateManager();//读取文件
+	int queryByNo(string sno);
+	void clearStudent();
+	int addStudent(UnderGraduate s);
+	int modifyStudent(string sno);
+	int deleteStudent(string sno);
+	int queryStudent(string sno);
+	void displayAll();
+	void dataManage();
+	void dataSave();
+	void dataRead();
+	~UnderGraduateManager();//写入文件
+};
+UnderGraduateManager::UnderGraduateManager() {
+	dataRead();
+}
+int UnderGraduateManager::queryByNo(string sno) { // 查找，有：i， 无： -1
+	for (int i = 0; i <= top; i++)
+		if (undergraduates[i].getStudentNo() == sno)
+			return i;
+	return -1;
+}
+void UnderGraduateManager::clearStudent() {//停止检索最后一个元素，相当于删除元素
+	top = -1;
+}
+int UnderGraduateManager::addStudent(UnderGraduate s) {//若不存在该元素（return -1），则元素数+1，保存至文件
+	int p = queryByNo(s.getStudentNo());
+	if (p == -1) {
+		top++;
+		undergraduates[top] = s;
+		dataSave();
+		return 1;
+	}
+	else {
+		cout << "existed!" << endl;
+		return 0;
+	}
+}
+int UnderGraduateManager::modifyStudent(string sno) {//若存在该元素（return ！= -1），则修改属性，保存至文件
+	int p = queryByNo(sno);
+	if (p == -1) {
+		cout << "Not exist!" << endl;
+		return 0;
+	}
+	else {
+		cout << "please input new detials" << endl;
+		undergraduates[p].inputData();
+		dataSave();
+		return 1;
+	}
+}
+int UnderGraduateManager::deleteStudent(string sno) {//删除元素，其他元素前移
+	int p = queryByNo(sno);
+	if (p == -1) {
+		cout << "Not exist!" << endl;
+		return 0;
+	}
+	else {
+		for (int i = 0; i < top; i++)
+			undergraduates[i] = undergraduates[i + 1];
+		top--;
+		cout << "Deleted!" << endl;
+		dataSave();
+		return 1;
+	}
+}
+int UnderGraduateManager::queryStudent(string sno) {
+	int p = queryByNo(sno);
+	if (p == -1) {
+		cout << "Not exist!" << endl;
+		return 0;
+	}
+	else {
+		cout << "exist!" << endl;
+		undergraduates[p].displayDetails();
+		return 1;
+	}
+}
+void UnderGraduateManager::displayAll() {
+	for (int i = 0; i <= top; i++) {
+		cout << "The NO." << i << "student's info:" << endl;
+		undergraduates[i].displayDetails();
+	}
+}
+UnderGraduateManager::~UnderGraduateManager() {
+	dataSave();
+}
+void UnderGraduateManager::dataManage() {
+	int choice = 1;
+	string sstudentNo;
+	UnderGraduate s;
+	while (choice != 0) {
+		cout << "**********************************" << endl;
+		cout << "\t\t undergraduate maintainace\n";
+		cout << "**********************************" << endl;
+		cout << "\n\t\t 1新增";
+		cout << "\n\t\t 2.修改";
+		cout << "\n\t\t 3.删除";
+		cout << "\n\t\t 4.查找";
+		cout << "\n\t\t 5.显示";
+		cout << "\n\t\t 6.全部删除";
+		cout << "\n\t\t 0.退出";
+		cout << endl;
+		cout << "**********************************" << endl;
+		cout << "Please take your choice: ";
+		cin >> choice;
+		switch (choice) {
+		case 1:
+			s.inputData();
+			addStudent(s);
+			break;
+		case 2:
+			cout << " Please input student's number:";
+			cin >> sstudentNo;
+			modifyStudent(sstudentNo);
+			break;
+		case 3:
+			cout << " Please input student's number:";
+			cin >> sstudentNo;
+			deleteStudent(sstudentNo);
+			break;
+		case 4:
+			cout << " Please input student's number:";
+			cin >> sstudentNo;
+			queryStudent(sstudentNo);
+			break;
+		case 5:
+			displayAll();
+			break;
+		case 6:
+			clearStudent();
+		default:
+			break;
+		}
+	}
+}
+void UnderGraduateManager::dataSave() {
+	fstream file("D:\\ProgramData\\vs\\design\\UGM.docx", ios::out);// !
+	for (int i = 0; i <= top; i++) {
+		file.write((char*)&undergraduates[i], sizeof(undergraduates[i]));
+	}
+	file.close();
+}
+void UnderGraduateManager::dataRead() {
+	UnderGraduate s;
+	top--;
+	fstream file("D:\\ProgramData\\vs\\design\\UGM.docx", ios::in); // !
+	while (1) {
+		file.read((char*)&s, sizeof(s));
+		if (!file) break;
+		top++;
+		undergraduates[top] = s;
+	}
+	file.close();
+}
+#endif //UNDERGRADUATE_MANAGER_H
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