A skeleton for a program that involves file I/O
(variations are possible)

# include <fstream>                           //include the header file for file I/O
# include <iostream>                         
using namespace std;
void main( )
{
            ifstream  input_file;        // “input_file” can be replaced by any other name
            ofstream output_file;      // “output_file” can be replaced by any other name
 
           //the following two lines will work if the name of the file is known/given:
            input_file.open (“text1.dat”);         //open input file named text1.dat
            output_file.open (“text2.dat”);       //open output file named text2.dat

//they will change to the following lines if the name is provided by the user:
                        char file_name_input[20], file_name_output[20];
                        cout<<”Enter the name of the input file:” ;
                        cin>>file_name_input;           
                        cout<<”Enter the name of the output file:” ;
                        cin>>file_name_output;
                        input_file.open (file_name_input);        //no double quotes
                        input_file.open (file_name_output);      //around the file name

if ( input_file.fail( ) ) // check for successful open
                        cout <<”Input file didn’t open”;
if (output_file.fail( ) )
                        cout<<”Output file didn’t open”;

input.file >> ……..  // read information (get inputs)
output.file << ……  //write information (output results)

          input_file.close ( );        //close files
          output_file.close ( );
}