import socket

class Netcat:

    """ Python 'netcat like' module """

    def __init__(self, ip, port):

        self.buff = ""
        self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
        self.socket.connect((ip, port))

    def read(self, length = 1024):

        """ Read 1024 bytes off the socket """

        return self.socket.recv(length)

    def read_until(self, data):

        """ Read data into the buffer until we have data """

        while not data in self.buff:
            self.buff += self.socket.recv(1024)

        pos = self.buff.find(data)
        rval = self.buff[:pos + len(data)]
        self.buff = self.buff[pos + len(data):]

        return rval

    def write(self, data):

        self.socket.send(data)

    def close(self):

        self.socket.close()

nc = Netcat('ppc.ctf.hackforces.com', 7081)
while True:
    x = str(nc.read())
    print(x)
    x = x[2:]
    print(x)
    g = x.split()
    print(g)
    a = int(g[0])
    b = int(g[2])
    c = a+b
    print(a, b, c)
    print(str(c).encode() + b'\x0a')
    nc.write(str(c).encode() + b'\x0a')
    print("!!!")