Reverse the Content of a File and Store it in Another File Python (original) (raw)

Last Updated : 16 Jan, 2026

Given a text file. The task is to reverse as well as stores the content from an input file to an output file. This reversing can be performed in three ways.

**Full reversing: Reverse all characters in the file completely.
**Line-wise Reversing: Reverse the order of lines in the file.
**Word to word reversing: Reverse the order of words in each line.

**Example: Full Reversing

**Input:
Hello Geeks
for geeks!

**Output:
!skeeg rof
skeeG olleH

**Example 2: Line-wise Reversing

**Input:
Hello Geeks
for geeks!

**Output:
for geeks!
Hello Geeks

**Example 3: Word to word reversing

**Input:
Hello Geeks
for geeks!

**Output:
Geeks Hello
geeks! for

Sample Input File:

python-reverse-file-input

file.txt

Full Reversing Using String Slicing

This method reads the entire file as a single string and reverses it using Python slicing. It is simple and fast but not suitable for very large files due to memory usage.

Python `

with open("file.txt", "r") as infile: data = infile.read()

with open("output1.txt", "w") as outfile: outfile.write(data[::-1])

**Output

python-reverse-file-output-1

output1.txt

**Explanation:

**read(): Reads the entire file as a string
**data[::-1]: Reverses all characters
**write(): Writes reversed content to output file

Reversing Order of Lines Using readlines()

This approach reverses the order of lines instead of characters. It reads all lines into a list and reverses the list.

Python `

with open("file.txt", "r") as infile: lines = infile.readlines()

with open("output2.txt", "w") as outfile: outfile.writelines(lines[::-1])

**Output

python-reverse-file-output-2

output2.txt

**Explanation:

**readlines(): Reads file into a list of lines
**lines[::-1]: Reverses line order
**writelines(): Writes reversed lines

Word-to-Word Reversing

This method reverses words in each line while keeping line order intact. Useful when sentence structure must be preserved.

Python `

with open("file.txt", "r") as infile, open("output3.txt", "w") as outfile: for line in infile: outfile.write(" ".join(line.split()[::-1]) + "\n")