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# Twice the Trouble
بسم الله الرحمن الرحيم
challenge
In this challenge, we are provided with a Python script that encrypts a flag using the XOR operation. The task is to decipher the flag by satisfying a mathematical condition based on user input.
### Let's analyze the code
The provided Python script consists of several functions:
1.
```
**`xor_encrypt_decrypt(input_str, key)`**:
```
```
* This function performs the XOR operation on each character of the input string using a given key.
```
2\.
```
**`get_flag()`**:
* This function contains the encoded flag represented as a list of integers. It uses an XOR key (13) to decode the flag and returns it.
```
3\.
```
**`compare_numbers(num1, num2)`**:
* This function compares the magnitudes of two numbers. It checks if the absolute value of the first number is exactly twice the absolute value of the second number.
```
4\.
```
**`main()`**:
* The entry point of the program. It generates random numbers, takes user input for two numbers, and calls the `compare_numbers` function. If the comparison is successful, it reveals the flag.
```
### Solving the Challenge
To successfully retrieve the flag, we need to provide two numbers (`num1` and `num2`) such that: abs(num1)=2×abs(num2)\text{abs(num1)} = 2 \times \text{abs(num2)}abs(num1)=2×abs(num2)
For example, if we choose:
* **num1 = 10**
* **num2 = 5**
This satisfies the condition since `10 = 2 * 5`.
### Flag Retrieval
When the condition is met, the program will call `get_flag()`, which returns the decoded flag.
####
### Flag
```
QUESTCON{d0ubl3_tr0ubl3}
```
