2023 5 17

xuxingkai / 2023-05-17 / 原文

#include <iostream>
#include <fstream>
using namespace std;
bool prime(int x)
{
    for (int i = 2; i * i <= x; i++)
    {
        if (x % i == 0)
            return false;
    }
    return true;
}
int main()
{
    ofstream ofs;
    ofs.open("D:\\VisualStudio2022\\Prime.txt", ios::out);
    if (!ofs)
    {
        cout << "文件打开失败" << endl;
        return 0;
    }
    for (int i = 2; i <= 100; i++)
    {
        if (prime(i))
            ofs << i<<" ";
    }
    ofs.close();
    return 0;
}

#include <iostream>
#include <fstream>
using namespace std;
string s;
int main()
{
    ofstream ofs;
    cout << "请输入文件名：";
    cin >> s;
    ofs.open(s, ios::out);
    if (!ofs)
    {
        cout << "文件打开失败" << endl;
        return 0;
    }
    int n, x, y, z;
    cout << "输入点的个数：";
    cin >> n;
    for (int i = 0; i < n; i++)
    {
        cin >> x >> y >> z;
        ofs << x << " " << y << " " << z << " " << endl;
    }
    ofs.close();
    cout << "读取坐标：" << endl;
    ifstream ifs;
    ifs.open(s, ios::in);
    if (!ifs)
    {
        cout << "文件打开失败" << endl;
        return 0;
    }
    char buff[1024];
    while(ifs.getline(buff,sizeof(buff)))
    {
        cout<<buff<<endl;
    } 
    ifs.close();
    return 0;
}