#!/usr/bin/env python2.6 # # Copyright (C) 2011 The Android Open Source Project # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. # # # Generates a table of prime numbers for use in BasicHashtable.cpp. # # Each prime is chosen such that it is a little more than twice as large as # the previous prime in the table. This makes it easier to choose a new # hashtable size when the underlying array is grown by as nominal factor # of two each time. # def is_odd_prime(n): limit = (n - 1) / 2 d = 3 while d <= limit: if n % d == 0: return False d += 2 return True print "static size_t PRIMES[] = {" n = 5 max = 2**31 - 1 while n < max: print " %d," % (n) n = n * 2 + 1 while not is_odd_prime(n): n += 2 print " 0," print "};"