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/* The Computer Language Shootout
http://shootout.alioth.debian.org/
contributed by Isaac Gouy
*/
object nsieve {
def nsieve(m: Int, isPrime: Array[Boolean]) = {
for (i <- Iterator.range(2, m)) isPrime(i) = true
var count = 0
for (i <- Iterator.range(2, m)) {
if (isPrime(i)) {
var k = i+i
while (k < m) { isPrime(k) = false; k += i }
count += 1
}
}
count
}
def main(args: Array[String]) {
val n = Integer.parseInt(args(0))
val m = (1<<n)*10000
val flags = new Array[Boolean](m+1)
def printPrimes(m: Int) {
def pad(i: Int, width: Int) = {
val s = i.toString
List.range(0, width - s.length)
.map((i) => " ") .foldLeft("")((a,b) => a+b) + s
}
Console.println("Primes up to " + pad(m, 8) + pad(nsieve(m, flags), 9))
}
printPrimes(m)
printPrimes( (1<<n-1)*10000 )
printPrimes( (1<<n-2)*10000 )
}
}
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