46 lines
1.4 KiB
Java
46 lines
1.4 KiB
Java
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/*
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This is java program to implement Wheel Seive method to generate the prime numbers from 2 to the given limit. This algorithm reduces the time by checking only till n^2.
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*/
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//This is a sample program to print all the prime numbers between 2 and n
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import java.util.LinkedList;
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import java.util.Scanner;
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public class Sieve_Method
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{
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public static LinkedList<Integer> sieve(int n)
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{
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if(n < 2)
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return new LinkedList<Integer>();
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LinkedList<Integer> primes = new LinkedList<Integer>();
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LinkedList<Integer> nums = new LinkedList<Integer>();
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for(int i = 2; i <= n; i++)
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{
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//unoptimized
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nums.add(i);
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}
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while(nums.size() > 0)
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{
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int nextPrime = nums.remove();
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for(int i = nextPrime * nextPrime; i <= n; i += nextPrime)
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{
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nums.removeFirstOccurrence(i);
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}
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primes.add(nextPrime);
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}
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return primes;
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}
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public static void main(String args[])
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{
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System.out.println("Enter the upper bound : ");
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Scanner sc = new Scanner(System.in);
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int end = sc.nextInt();
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System.out.println(sieve(end));
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sc.close();
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}
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}
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/*
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Enter the upper bound :
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70
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[2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67]
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