Created
April 23, 2012 01:06
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Simple prime number generator in java
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import java.util.BitSet; | |
public class SieveOfEratosthenes { | |
/** | |
* @param args | |
*/ | |
public static void main(final String[] args) { | |
final int length = 2000000; | |
final BitSet sieve = new BitSet(length); | |
long sum = 0; | |
sieve.flip(2, sieve.size()); | |
for (int i = 0; i < sieve.size(); i++) { | |
if (sieve.get(i)) { | |
for (int j = i * 2; j < sieve.size(); j += i) { | |
sieve.set(j, false); | |
} | |
} | |
} | |
for (int i = 0; i < sieve.size(); i++) { | |
if (sieve.get(i)) { | |
sum += i; | |
} | |
} | |
System.out.println(sum); | |
} | |
} |
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