I am lost on how to read from file and output to file?

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Code:

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I am not sure how to read from file.  For example, i have a file said
2
1 2
3
1 2 3

if i need to read the first number represent how many number and 2nd line show the number 1 and 2
when i read 3rd line it show there are 3 number so the 4th row show 1 2 3 is the 3 number how can i do it?
when i program it i program something like this but it doesn't work?  Instead it only show
2 number of interger
1 number of interger 2
3 number of interger
1 number of interger 2 3

how can i do it so that it will read first line and 3rd line (2 and 3) as an variable of number_of_interger.  And read 2nd and 4th line (1, 1, 2, and 3) as number?

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Code:

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[/PHP]

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#include <fstream>
#include <conio.h>
#include <iostream>
#include <iomanip>

#define in_file "input.txt"
#define out_file "output.txt"
using namespace std;
void main()
{
ifstream ins;
ofstream outs;

//string scores;
char number_of_interger, number;

ins.open(in_file);
outs.open(out_file);

while (!ins.eof())
{
ins >> number_of_interger;
cout << number_of_interger << "number"
<< " of interger";
ins.get(card_scores);

while (number != '\n')
{
outs << number;
cout << number;
ins.get(number);
}
cout << number;
outs << number;
}
outs << number;
ins >> number_of_interger;
getch();
ins.close();
outs.close();
}

use codetags!
use int main(), not void main()!

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Try this.

Code:

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#include <fstream>
#include <conio.h>
#include <iostream>
#include <iomanip>
#include <string>
using namespace std;

const string in_file( "input.txt" );
const string out_file( "output.txt" );
int main()
{
  ifstream ins;
  ofstream outs;

  //string scores;
  int number_of_integer, number;

  ins.open(in_file.c_str());
  outs.open(out_file.c_str());

  while (ins >> number_of_integer)
  {
      cout << number_of_integer << " number"
      << " of integer" << endl;

      for (int i=0; i<number_of_integer; ++i)
      {
        ins >> number;
        outs << number << " ";
        cout << number << " ";
      }
      cout << endl;
  }
  cin.get();
  ins.close();
  outs.close();
}

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Quote:

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I am lost on how to read from file and output to file?

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Since that is the only part of your post that I can understand:

Code:

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#include<fstream>
#include<iostream>
#include<string>

using namespace std;

int main()
{
        ofstream outFile("C:\\Beginning C++\\data.txt");
        outFile<<"1 "<<2<<" "<<3<<"\n"<<"4 5";
        outFile.close();

        ifstream inFile("C:\\Beginning C++\\data.txt");
        if(!inFile)
        {
                cout<<"no such file"<<endl;
                return 1;
        }

        int data[10] = {0};
        int i = 0;
        while(!inFile.eof())
        {
                inFile>>data[i];
                i++;
        }
       
        int num = sizeof data/sizeof data[0];
        for(int k = 0; k<num; k++)
        {
                if(data[k] != 0)
                        cout<<data[k]<<" "<<endl;
        }
       
        return 0;
}

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You might as well write your post using your native language--English isn't working for you.