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import java.util.Scanner;

public class Eratosthenes {
    
  public static void main(String[] args) {
    new Eratosthenes().top();  }
    
  void top() {
    int   max        = eingabe("Max");
    int[] alleZahlen = init(max);
    sieben(alleZahlen);
    ausgabe(alleZahlen);  }
   
  void sieben(int[] alleZahlen) {
    int i = 0; 
    while(i < Math.sqrt(alleZahlen.length + 2)) { // sqrt = Quadratwurzel
        if(alleZahlen[i] > 0) {
        vielfacheLoeschen(alleZahlen, i);  }
      i = i + 1;  }    
  }

  void vielfacheLoeschen(int[] alleZahlen, int i) {
    int zahl = alleZahlen[i];
    int lIdx = i + zahl;
    while(lIdx < alleZahlen.length) {
      alleZahlen[lIdx] = 0;
      lIdx = lIdx + zahl;  }   
  }

  void ausgabe(int[] alleZahlen) {
    for(int z : alleZahlen) {
      if(z > 0) {
        System.out.println(z);  }
    }
  }

  int[] init(int max) {
    int[] arr = new int[max - 1];
    int i = 0;
    while( i < arr.length) {
      arr[i] = i + 2;
      i = i + 1;  }
    return arr;  }
   
  int eingabe(String string) {
    System.out.println(string + " :");
    Scanner sc = new Scanner(System.in);
    return sc.nextInt();  }

} // end class Eratosthenes
 
                

from math import sqrt
def eratosthenes(size):
    p=[]
    for i in range(2,size+1):
        p.append(i)
    z=2
    while z < sqrt(size):
        for t in p:
            if t>0:
                z=t
                break
   
        for k in p:
            if k%z==0:
                dump=p.remove(k)
        
    return p

print eratosthenes(10000)
                

public class Erasthotenes {
   public static void main(String[] args) {
     int n = 0; 
     try {
       n = Integer.parseInt(args[0]);
     } catch(Exception e) { }
     if(n < 2) n = 10000; 
     int[] p = new int[n+1]; 
     for(int i = 2; i <= n; i++) p[i] = i;
     for(int k = 2; k*k <= n; k++) 
       for(int i = 2*k; i <= n; i += k) 
         p[i] = 0; System.out.print("2");
     for(int i = 3; i <= n; i++)
       if(p[i] != 0)
         System.out.print(", " + i); System.out.println(); } }  	
                

function sieveOfEratosthenes(max) {
   var numbers = [], 
       primes = [],
       x = 2;
   
   for(x; x <= max; x++) numbers.push(x);
   
   while (numbers.length > 0) {
      primes.push(numbers.shift());
      for (x = 0; x <= numbers.length; x++)
         if (numbers[x] % primes[primes.length - 1] == 0) numbers.splice(x, 1);      
   }
   return primes;   
}

console.log(sieveOfEratosthenes(1000));
                

Lösung von: Lisa Salander (Heidi-Klum-Gymnasium Bottrop)

// C++ 14 || VS-2022
#include <iostream>
#include <vector>
#include <algorithm>

std::vector<int> get_primes(int n) {
    std::vector<int> v{};
    for (size_t i{ 2 }; i < n; i++) v.push_back(i);
    auto q{ sqrt(n) };
    while (q--) {
        for (size_t i{ 0 }; i < v.size(); i++) {
            auto it{ std::remove_if(v.begin(), v.end(), [&i, &v](int k) { return (k != v[i] && k % v[i] == 0); }) };
            v.erase(it, v.end());
        }
    }
    return v;
}

void print(const std::vector<int>& v) {
    for (auto it{ v.begin() }; it != v.end() - 1; it++)
        std::cout << *it << ", ";
    std::cout << v.back() << "\n";
}

int main() {
    print(get_primes(100));
}
                

Lösung von: Jens Kelm (@JKooP)