打卡5

#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

// 定义教师结构体
struct Teacher {
    int id;         // 工号
    string name;    // 姓名
    char gender;    // 性别
};

int main() {
    int N;
    cout << "请输入教师信息的个数：";
    cin >> N;

    // 创建文件输出流
    ofstream ofs("teacher.dat", ios::binary);
    if (!ofs) {
        cerr << "打开文件失败！" << endl;
        return -1;
    }

    // 依次输入教师信息，并写入文件
    for (int i = 0; i < N; i++) {
        Teacher t;
        cout << "请输入第" << i + 1 << "个教师的工号、姓名和性别：";
        cin >> t.id >> t.name >> t.gender;
        ofs.write((char*)&t, sizeof(Teacher));
    }

    ofs.close();

    // 读取文件内容，验证是否写入成功
    ifstream ifs("teacher.dat", ios::binary);
    if (!ifs) {
        cerr << "打开文件失败！" << endl;
        return -1;
    }

    Teacher t;
    while (ifs.read((char*)&t, sizeof(Teacher))) {
        cout << "工号：" << t.id << "\t姓名：" << t.name << "\t性别：" << t.gender << endl;
    }

    ifs.close();

    // 修改某位教师的信息
    int modifyId;
    cout << "请输入要修改的教师的工号：";
    cin >> modifyId;

    // 创建文件输入流和输出流
    ifstream ifs2("teacher.dat", ios::binary);
    if (!ifs2) {
        cerr << "打开文件失败！" << endl;
        return -1;
    }
    ofstream ofs2("teacher2.dat", ios::binary);
    if (!ofs2) {
        cerr << "打开文件失败！" << endl;
        return -1;
    }

    while (ifs2.read((char*)&t, sizeof(Teacher))) {
        if (t.id == modifyId) {  // 如果是要修改的教师，则重新输入信息
            cout << "请输入修改后的教师的工号、姓名和性别：";
            cin >> t.id >> t.name >> t.gender;
        }
        ofs2.write((char*)&t, sizeof(Teacher));  // 将教师信息写入新文件
    }

    ifs2.close();
    ofs2.close();

    // 删除原文件，并将新文件名改为原文件名
    remove("teacher.dat");
    rename("teacher2.dat", "teacher.dat");

    // 输出修改后的教师信息
    ifstream ifs3("teacher.dat", ios::binary);
    if (!ifs3) {
        cerr << "打开文件失败！" << endl;
        return -1;
    }

    while (ifs3.read((char*)&t, sizeof(Teacher))) {
        cout << "工号：" << t.id << "\t姓名：" << t.name << "\t性别：" << t.gender << endl;
    }

    ifs3.close();

    return 0;
}

#include <iostream>
#include <fstream>
#include <string>
#include<iostream>
#include<algorithm>
using namespace std;
#include<vector>
//二进制
int main() 
{
    ifstream ifs("f1.txt", ios::binary);
    ofstream ofs("f2.txt", ios::binary);
    if (!ifs)
    {
        cout << "文件打开失败" << endl;
        return -1;
    }
    vector<int> v;
    int num;
    while (ifs.read((char*)&num, sizeof(int)))
    {
        v.push_back(num);
    }
    ifs.close();
    sort(v.begin(), v.end());
    for (auto i : v)
    {
        cout << i << ' ';
        ofs.write((char*)&i, sizeof(int));
    }
    ofs.close();
    return 0;
}



#include <iostream>
#include <fstream>
#include <string>
#include<iostream>
#include<algorithm>
using namespace std;
#include<vector>
//文本文件
int main() 
{
    ifstream ifs("f1.txt", ios::in);
    ofstream ofs("f2.txt", ios::out);
    if (!ifs)
    {
        cout << "文件打开失败" << endl;
        return -1;
    }
    vector<int> v;
    int num;
    while (ifs >> num)
    {
        v.push_back(num);
    }
    ifs.close();
    sort(v.begin(), v.end());

    for (int i = 0; i < v.size(); i++)
    {
        ofs << v[i] << " ";
    }
    ofs.close();
    return 0;
}

#include <fstream>
#include <string>
#include<iostream>
#include<algorithm>
using namespace std;
#include<vector>
int main() 
{
    ifstream ifs("mesage.txt", ios::in);
    string line;
    int linenum=0;
    int wordnum = 0;
    while (getline(ifs, line)) {

        ++linenum;
        for (int i = 0; i < line.length(); i++)
        {
            if (line[i] == ' ')
            {
                ++wordnum;
            }
        }
    }
    ifs.close();
    cout << "单词的数目：" << wordnum << endl;
    cout << "行数：" << linenum << endl;
    return 0;
}