Low Logic

Created: July 31, 2025 9:42 AM Difficulty: Very Easy Category: hardware

Analyzing the challenge Docs we get circuit diagram and a csv with what it looks is the input of the circuit.

Here we have transistors and resistances, if we look closely we can discover that this exactly assembly of resistances and transistors let us make logic gates in this case we get one or gate and two and gates which makes the following logic diagram

Then to solve this challenge we need to write a script (in this case written on python) to model the gates flow by getting the inputs located on the csv , so the script could look like this

def open_file(url: str) -> list[str]:
    with open(url) as f:
        buffer = f.read()
    return buffer.split('\n')[1:-1]

def operations(entry: str) -> None:
    bits: int = [int(i) for i in entry.split(',')]
    return (bits[0] and bits[1]) or (bits[2] and bits[3])
    

if __name__ == "__main__":
    bits = [operations(i) for i in open_file('input.csv')]
    bit_string = ''.join(str(b) for b in bits)
    chars = ''.join([chr(int(bit_string[i:i+8], 2)) for i in range(0, len(bit_string), 8)])
    print(chars) 

This simple script in the open_file function opens the csv file saves the input on a list by splitting it by test cases (here we use the \n char) and removing the first and the last item. In other hand, operations get the entry by each test case and operate each bit. Lastly, the code just convert from bytes to string, revealing our flag.

Home