YCEP 2025 - Sort and Read

Challenge Description

Description

I unintentionally scrambled the content of a file, but thankfully the lines are previously labelled with their corresponding line numbers. Can you help me sort them?

Submit the flag in the following format: YCEP25{flag}

• Author: Jun Wei
• Category: misc
• Difficulty: easy
• Discord: syn3pz

Files

• file.txt

Sort and Read - Solution

We are given a file file.txt with the randomly sorted contents.

The characters on the right represent the individual characters that form the flag, when sorted correctly.

They are all accompanied by a respective line number.

To sort them, we can run sort -n file.txt.

Alternatively, participants can (and should) explore scripting to display the flag in a single line.

Example python script:

input = "file.txt"
 
with open(input, "r") as file:
    lines = file.readlines()
 
    lines.sort(key=lambda line: int(line.split()[0])) # Sort lines by the leftmost number in each line
    
    flag = "" 
 
    for line in lines:
        parts = line.split()
        
        if len(parts) > 1:  
            char = parts[1]
            flag += char 
 
    print("Flag:", flag)

Flag: YCEP25{5UCC355FUL1Y_50RT3D}