{"post":"

# Understanding the question

In this program, we have to create a file, write something to that file, and then extract that data from that file and print it on our screen.

# Approaching the question

To process a file in C++, we can use the functions provided in the <fstream> header file. This includes functions for opening, reading, and writing to text files.
Follow these steps to process a file:\n
1. Open the file: Use the open() function and specify the mode (e.g. ios::in, ios::out) to tell the compiler whether to read from or write to the file.
2. Work on the file: Use the appropriate functions to read and write to the file as needed.
3. Close the file: After you have finished working with the file, be sure to close it before terminating the program.
\n
To write to a file, you can use the cascade operator (<<) or the put() function to write character by character.
To read from a file, you can use the cascade operator (>>) to read word by word, or use the getline() function to read line by line and the getchar() function to read character by character.
Note that the <fstream> header file is a superset of <iostream>, so you don't need to include <iostream> separately.

Code

#include <iostream>\n#include <fstream>\nusing namespace std;\n\nint main() {\n  fstream ob;\n\n  ob.open(\"test.txt\", ios::out);  // opening file in writing mode\n\n  ob << \"hello world\\n\";  // writing data to file\n\n  ob << \"this is my first file\";\n\n  ob.close();  // closing the file\n\n  ob.open(\"test.txt\", ios::in);  // again opening the file but in reading mode\n\n  while (!ob.eof()) {\n    string str;\n\n    ob >> str;  // reading word by word from file and storing in str\n\n    cout << str << \"\\n\";  // printing str\n  }\n\n  ob.close();  // closing the file after use\n\n  return 0;\n}\n\n

Output

$\"\"$

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