---

import socket
import json
import re

HOST = 'tasks.duckerz.ru'
PORT = 30009

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.settimeout(120.0)
s.connect((HOST, PORT))

data = b""
try:
    while b"Send to Bob:" not in data:
        chunk = s.recv(4096)
        if not chunk:
            break
        data += chunk
except socket.timeout:
    pass

text = data.decode('utf-8', errors='ignore')
match = re.search(r'\{.*\}', text)
alice = json.loads(match.group())

p = int(alice['p'], 16)
g = int(alice['g'], 16)
A = int(alice['A'], 16)

print(f"[*] p = {p} ({p.bit_length()} бит)")
print(f"[*] g = {g}")
print(f"[*] A = {A}")

# Перебираем выражения a+b, a-b, a*b, a//b
# где a, b от 1 до 1000
print("[*] Перебираем выражения...")
found_expr = None
found_result = None

ops = ['+', '-', '*', '//']

for a in range(1, 1001):
    if a % 100 == 0:
        print(f"[*] a = {a}...")
    
    for b in range(1, 1001):
        for op in ops:
            expr_str = f"{a}{op}{b}"
            # Переводим строку в число (как байты)
            x = int.from_bytes(expr_str.encode(), 'big')
            
            if pow(g, x, p) == A:
                found_expr = expr_str
                found_result = eval(expr_str)
                print(f"\n[!!!] НАЙДЕНО! {expr_str} = {found_result}")
                break
        if found_expr:
            break
    if found_expr:
        break

if found_expr:
    # Отправляем результат
    payload = json.dumps({"answer": found_result})
    print(f"[*] Отправляем: {payload}")
    s.sendall((payload + "\n").encode())
    
    s.settimeout(15.0)
    try:
        while True:
            resp = s.recv(4096)
            if not resp:
                break
            decoded = resp.decode('utf-8', errors='ignore')
            print(f"[+] Ответ: {decoded}")
            if "DUCKERZ{" in decoded:
                print(f"\n[!!!] ФЛАГ: {decoded}\n")
                break
    except socket.timeout:
        print("[-] Таймаут")
else:
    print("\n[-] Выражение не найдено.")

s.close()