diff options
Diffstat (limited to 'ruby_1_8_6/sample/sieve.rb')
-rw-r--r-- | ruby_1_8_6/sample/sieve.rb | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/ruby_1_8_6/sample/sieve.rb b/ruby_1_8_6/sample/sieve.rb new file mode 100644 index 0000000000..e0bb21d640 --- /dev/null +++ b/ruby_1_8_6/sample/sieve.rb @@ -0,0 +1,14 @@ +# sieve of Eratosthenes +max = Integer(ARGV.shift || 100) +sieve = [] +for i in 2 .. max + sieve[i] = i +end + +for i in 2 .. Math.sqrt(max) + next unless sieve[i] + (i*i).step(max, i) do |j| + sieve[j] = nil + end +end +puts sieve.compact.join(", ") |