File: nsieve.ruby-2.ruby

package info (click to toggle)
jruby 9.4.8.0%2Bds-3
  • links: PTS, VCS
  • area: main
  • in suites: forky, sid, trixie
  • size: 89,244 kB
  • sloc: ruby: 548,574; java: 276,189; yacc: 25,873; ansic: 6,178; xml: 6,111; sh: 1,855; sed: 94; makefile: 78; jsp: 48; tcl: 40; exp: 12
file content (25 lines) | stat: -rw-r--r-- 459 bytes parent folder | download | duplicates (9)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
# The Computer Language Shootout
# http://shootout.alioth.debian.org/
# contributed by Pavel Valodzka

def nsieve(m)
  is_prime = Array.new(m, true)
  count = 0
  2.upto(m){|i|
    if is_prime[i]
      (2 * i).step(m, i){|v|
        is_prime[v] = false
      }
      count += 1
    end
  }
  return count
end

n = (ARGV[0] || 2).to_i
n = 2 if (n < 2)

3.times {|t|
  m = (1<<n-t)*10000
  printf("Primes up to %8d%9d\n", m, nsieve(m))  
}