#!/usr/bin/env python
from __future__ import print_function
import sys
from struct import pack,unpack

if sys.platform == "win32":
    import os, msvcrt
    msvcrt.setmode(sys.stdout.fileno(), os.O_BINARY)


class Mem:
    def __init__(self):
        self.low_water=0xffff
        self.high_water=0
        page=b'\0'*256
        self.mem=page*256
    def load_prg(self, fn):
        data=open(fn,'rb').read()
        start=unpack('<H',data[:2])[0]
        data=data[2:]
        end=min(0x10000,start+len(data))
        data=data[:end-start]
        self.low_water=min(self.low_water, start)
        self.high_water=max(self.high_water, end)
        self.mem=self.mem[:start]+data+self.mem[end:]

    def write(self, f):
        if self.low_water<self.high_water:
            f.write(pack('<H',self.low_water)+self.mem[self.low_water:self.high_water])
        else:
            f.write(pack('<H',0x0801))



m=Mem()
for fn in sys.argv[1:]:
    m.load_prg(fn)

try:
    fo=sys.stdout.buffer
except AttributeError:
    import sys
    fo=sys.stdout
m.write(fo)