从一个txt文件中读取数据写入到另一个txt文件。

读取时会自动将空格忽略，只读取数字。

#include <fstream>
using namespace std;

int main(int argc, char ** argv)
{
    int num;
    long double time;
    char kg;
    int a=1, b=2;
    struct timeval t_start, t_end;
    long double t;
    ifstream fin("/home/flk/fea_num6.txt",ios::app);//


    while (1)
    {
        sleep(1);
        cout.setf(ios::fixed,ios::floatfield);//十进制计数法，不是科学计数法
        cout.precision(2);//保留2位小数
        ofstream fout_num("/home/flk/fn_ext.txt",ios::app);
//        ofstream fout_kg("/home/flk/kg_ext.txt",ios::app);
        ofstream fout_time("/home/flk/time_ext.txt",ios::app);
        if(fin.is_open()&&fout_num.is_open()&&fout_time.is_open())
        {
            cout<<"open scueess"<<endl;
        } else{
            cout<<"open faile"<<endl;
        }
        fin>>num;
        cout<<"num: "<<num<<endl;
        fout_num<<num<<" ";
        fin>>time;
        cout<<"time: "<<time<<endl;
        fout_time<<time<<" ";

        if(fin.eof())
        {
            cout<<"finish"<<endl;
            fin.close();
            fout_time.close();
 //           fout_kg.close();
            fout_num.close();
            return 1;
        }

    }
   return 0;
}

本文地址：https://blog.csdn.net/m0_46345373/article/details/110718444