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Intellectual Conversation

Intellectual Conversation

  • Author: Aadhyanth

Encoding: convert each character to ascii and insert \u200b after that many characters

Decoding: find distance between 2 zero-width characters and convert take chr()

python code:

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def hide_flag_in_text(text, flag):
    zwsp = "\u200b"
    result = ""

    flag_index = 0
    char_count = 0

    for ch in text:
        result += ch
        char_count += 1

        # check if we've reached the ascii value position for current flag character
        if flag_index < len(flag) and char_count == ord(flag[flag_index]):
            result += zwsp
            flag_index += 1
            char_count = 0  # reset counter

    return result

def decode_flag_from_text(encoded_text):
    char_count = 0
    flag = ""

    for ch in encoded_text:
        if ch == '\u200b':
            flag += chr(char_count)
            char_count = 0
        else:
            char_count += 1

    return flag

# Usage
huge_text = """TRANSCRIPT-1

Discussion between Dr. Sarah Chen (Theoretical Physicist) and Prof. Marcus Rodriguez (Materials Science)
...
...
Prof. Rodriguez: Thank you, Sarah. I look forward to continuing this conversation as the field evolves.

[End of Transcript]
"""
flag = "CBCV{1nv151b1l1ty_0r_t1m3_c0ntr0l?}"
encoded_text = hide_flag_in_text(huge_text, flag)

print("Encoded text:")
print(encoded_text)

with open('transcript.txt', 'w', encoding='utf-8') as file:
    file.write(encoded_text)
    file.close()


with open('transcript.txt', 'r', encoding = 'utf-8') as file:
    data = file.read()
    print("\nDecoded flag:")
    print(decode_flag_from_text(data))

Output: Encoded text: Squeezed text (182 lines).

The flag found is:

CBCV{1nv151b1l1ty_0r_t1m3_c0ntr0l?}

Flag

CBCV{1nv151b1l1ty_0r_t1m3_c0ntr0l?}
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