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author | Jari Vetoniemi <jari.vetoniemi@indooratlas.com> | 2020-03-16 18:49:26 +0900 |
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committer | Jari Vetoniemi <jari.vetoniemi@indooratlas.com> | 2020-03-30 00:39:06 +0900 |
commit | fcbf63e62c627deae76c1b8cb8c0876c536ed811 (patch) | |
tree | 64cb17de3f41a2b6fef2368028fbd00349946994 /jni/ruby/benchmark/bm_so_nsieve.rb |
Fresh start
Diffstat (limited to 'jni/ruby/benchmark/bm_so_nsieve.rb')
-rw-r--r-- | jni/ruby/benchmark/bm_so_nsieve.rb | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/jni/ruby/benchmark/bm_so_nsieve.rb b/jni/ruby/benchmark/bm_so_nsieve.rb new file mode 100644 index 0000000..a65cc78 --- /dev/null +++ b/jni/ruby/benchmark/bm_so_nsieve.rb @@ -0,0 +1,35 @@ +# The Computer Language Shootout +# http://shootout.alioth.debian.org/ +# +# contributed by Glenn Parker, March 2005 +# modified by Evan Phoenix, Sept 2006 + +def sieve(m) + flags = Flags.dup[0,m] + count = 0 + pmax = m - 1 + p = 2 + while p <= pmax + unless flags[p].zero? + count += 1 + mult = p + while mult <= pmax + flags[mult] = 0 + mult += p + end + end + p += 1 + end + count +end + +n = 9 # (ARGV[0] || 2).to_i +Flags = ("\x1" * ( 2 ** n * 10_000)).unpack("c*") + +n.downto(n-2) do |exponent| + break if exponent < 0 + m = (1 << exponent) * 10_000 + # m = (2 ** exponent) * 10_000 + count = sieve(m) + printf "Primes up to %8d %8d\n", m, count +end |