c++ - Input line by line from an input file and tokenize using strtok() and the output into an output file -

what trying input file line line , tokenize , output output file.what have been able input first line in file problem unable input next line tokenize saved second line in output file,this far fro inputing first line in file.

#include <iostream> #include<string>    //string library #include<fstream>    //i/o stream input , output library  using namespace std; const int max=300;    //intialization constant called max line length  int main() {    ifstream in;     //delcraing instream    ofstream out;    //declaring outstream     char oneline[max];   //declaring character called oneline length max     in.open("infile.txt");  //open instream    out.open("outfile.txt");  //opens outstream    while(in)    {      in.getline(oneline,max); //get first line in instream      char *ptr;      //declaring character pointer     ptr = strtok(oneline," ,");     //pointer scans first token in line , removes delimiters     while(ptr!=null)    {      out<<ptr<<" ";    //outputs file copy file     ptr=strtok(null," ,");     //pointer moves second token after first scan on     }     }    in.close();      //closes in file    out.close();      //closes out file      return 0; } 

the c++ string toolkit library (strtk) has following solution problem:

#include <iostream> #include <string> #include <deque> #include "strtk.hpp"  int main() {    std::deque<std::string> word_list;    strtk::for_each_line("data.txt",                         [&word_list](const std::string& line)                         {                            const std::string delimiters = "\t\r\n ,,.;:'\""                                                           "!@#$%^&*_-=+`~/\\"                                                           "()[]{}<>";                            strtk::parse(line,delimiters,word_list);                         });     std::cout << strtk::join(" ",word_list) << std::endl;     return 0; } 

more examples can found here