50 lines
1.0 KiB
Java
50 lines
1.0 KiB
Java
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/**
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*
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* @author Varun Upadhyay (https://github.com/varunu28)
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*
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*/
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public class SieveOfEratosthenes {
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/**
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* This method implements the Sieve of Eratosthenes Algorithm
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*
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* @param n The number till which we have to check for prime
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* Prints all the prime numbers till n
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**/
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public static void findPrimesTillN(int n) {
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int[] arr = new int[n+1];
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for (int i=0;i<=n;i++) {
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arr[i] = 1;
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}
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arr[0] = arr[1] = 0;
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for (int i=2;i<=Math.sqrt(n);i++) {
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if (arr[i] == 1) {
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for (int j=2;i*j <= n;j++) {
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arr[i*j] = 0;
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}
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}
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}
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for (int i=0;i<n+1;i++) {
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if (arr[i] == 1) {
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System.out.print(i + " ");
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}
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}
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System.out.println();
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}
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// Driver Program
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public static void main(String[] args) {
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int n = 100;
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// Prints 2 3 5 7 11 13 17 19 23 29 31 37 41 43 47 53 59 61 67 71 73 79 83 89 97
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findPrimesTillN(n);
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}
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}
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