def read_nums(filename):
    ''' 读取文件中讲所有的数字形成列表
    素数是按照大小顺序已经排序好的。
    '''
    l = []
    with open(filename,'r',encoding='utf-8') as f:
        for line in f:
            l.extend([int(x) for x in line.split()])
    return l

def binary_search(nums, n):
    ''' 二分查找
    https://www.zhihu.com/question/36132386/answer/530313852
    '''
    first = 0
    last = len(nums)
    while first < last:
        mid = first + (last - first) // 2
        if nums[mid] < n:
            first = mid + 1
        else:
            last = mid
    return first

def get_range(nums, index, end_n):
    '''
    找到符合范围条件的素数
    '''
    l = [nums[index]]
    while 1:
        index += 1
        n = nums[index]
        if n > end_n:
            break
        else:
            l.append(n)
    return l

def search_nums(nums, start, end):
    """
    返回符合条件的8个质数
    """
    start_index = binary_search(nums, start)
    return get_range(nums, start_index, end)

def main(start,end):
    nums = read_nums('p.txt')
    return search_nums(nums, start,end)

if __name__ == '__main__':
    print(main(9165693650, 9165693700))

import socket
import time
import re
import random
from prime import read_nums, search_nums

# 根据题目的前是个字符来选择答案
ans = {
    "支持 WebP 图片": '65',
    "访问网址 “http": 'ctf.xn--4gqwbu44czhc7w9a66k.com',
    "视频 bilibil": '418645518',
    "每个 Android": 'cn.edu.pku.pkurunner',
    "北京大学某实验室曾开": '10.14778/2002974.2002976',
    "在第一届 PKU G": '0',
    "我有一个朋友在美国，": lambda:random.choice([20103,20104,20146,20147,20149,20166]),  # 这个题不会呀！
    "在第一届 PKU G": lambda level: 300+int(level**1.5)*100
}

# 先把后面的要用素数都读取提起准备好，这样只用读一遍。
primes = read_nums('p.txt')
print("read nums ready!")

def range_nums(content):
    """ 得到素数题的范围
    """
    start,end =  list(map(int, re.findall(r'\d{10}', content)))
    return start,end

def wait_until(conn, size=1024):
    """ recv 直到问题内容结束
    """
    r = conn.recv(size).decode()
    while r[-2] != '>':
        r += conn.recv(size).decode()
    return r

def main():
    conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    conn.settimeout(5)
    conn.connect(('prob01.geekgame.pku.edu.cn',10001))

    # send token
    r = conn.recv(4096).decode()
    print(r)
    s = b'<your token is here!>\n'
    print(s)
    conn.send(s)

    # 开始答题
    r = conn.recv(4096).decode()
    print(r,end='')
    s = '急急急\n'
    print(s)
    conn.send(s.encode())

    i=0
    while i<7: # 每次7道题目
        r = wait_until(conn)
        print(r, end="")
        # print('repr:',repr(r[-5:]))

        if r.find("质数") == -1:
            index = r.index('题：')
            k = r[index+2:index+12]
            s = ans.get(k,'unknow!')
            if type(s) is not str:
                if k.startswith('在'):
                    # 关于电子游戏概论的题目
                    level = int(re.findall(r'\d+',r)[-1])
                    print('level', level)
                    s = s(level)
                else:
                    # 从MAC地址到邮编的题
                    s = s()
        else:
            # 是找素数的题
            nums = search_nums(primes, *range_nums(r))
            print(nums)
            s =  random.choice(nums)

        conn.send("{}\n".format(s).encode())
        print(s)
        time.sleep(0.1) # 重要！否则会影响整个流程正常的发送和接收。

        i+=1

    # 返回最后的得分结果
    r = conn.recv(1024).decode()
    while r.find('！') == -1:
        r += conn.recv(1024).decode()
    print(r)
    return r


if __name__ == '__main__':
    # 只有不停的试才能成功呀！
    while 1:
        result = main()
        # if input('y/n: ') != 'y':
        #     print("End.")
        #     break
        if result.find('你共获得了 100 分') != -1:
            print('GOAL!'*10)
            break
        time.sleep(8)  # 有连接频率限制

import base64

def rot13(content):
    r = []
    for c in content:
        n = ord(c)
        if n >= ord('a') and n <= ord('m'):
            n += 13
        elif n >= ord('A') and n <= ord('M'):
            n += 13
        elif n >= ord('n') and n <= ord('z'):
            n -= 13
        elif n >= ord('N') and n <= ord('Z'):
            n -= 13
        elif n >= ord('5') and n <= ord('9'):
            n -= 5
        elif n >= ord('0') and n <= ord('4'):
            n += 5
        r.append(chr(n))
    return ''.join(r)
        
if __name__ == '__main__':
    result = base64.b64decode(rot13('MzkuM8gmZJ6jZJHgnaMuqy4lMKM4'))
    print(result)

import json

def read_json_file(filename):
    with open(filename,'r') as f:
        json_flag = json.loads(f.read())
    return json_flag

def main():
    json_flag = read_json_file('flag.json')
    # print(json_flag)
    i = 0
    while i<2640:
        # 观察到那个表列项是A到K是11个。
        if (i+1) % 11 == 0:
            endchar = '\n'
        else:
            endchar = ''
        c = json_flag.get(str(i), ' ')
        if c == ' ':
            w = ' '
        else:
            w = '▉'
        print(w, end=endchar)
        i += 1

if __name__ == '__main__':
    main()