dirty divide-and-conquer python function list_contains_fast.py

list_contains_fast.py

def list_contains_fast(largelist,startwithstr):

        listsize=len(largelist)
        #print "list_contains_fast"+str(listsize)

        if listsize <= 500:
                for listentry in largelist:
                        if startwithstr.startswith(listentry):
                                return True
                return False

        currentpick_index=int(listsize/2)
        currentpick=largelist[currentpick_index]
        currentpick_len=len(currentpick)
        compare_len=len(currentpick)

        if currentpick_len > len(startwithstr):
                compare_len = len(startwithstr)

        if currentpick.startswith(startwithstr) == True:
                return True

        if startwithstr[0:compare_len] > largelist[currentpick_index][0:compare_len]:
                return list_contains_fast(largelist[currentpick_index-1:],startwithstr)
        else:
                return list_contains_fast(largelist[:currentpick_index+1],startwithstr)