import os
import glob
import re

dlist = glob.glob('RD00??')
dlist.sort()
currentfolder = os.getcwd()
for folder in dlist:
    n = int(re.sub(r'\D',"",folder))
    os.chdir(currentfolder+'/'+folder)
    for filename in os.listdir("."):
      if filename.startswith("RD%04i"%n):
         os.rename(filename, 'MergerHalos'+filename[6:])
    lines = open('MergerHalos.txt').readlines()
    f=open('MergerHalos.txt','w')
    for line in lines:
        line =  line.replace("MergerHalos","./RD%04i/MergerHalos"%n)
        f.write(line)
    f.close()
    os.chdir(currentfolder)