Initial commit

PrimeFinder.java

+import java.util.ArrayList;
+import java.util.List;
+
+public class PrimeFinder
+{
+    public static void main(String[] args)
+    {
+        long startTime = System.nanoTime();
+
+        int threadsNum = 5;
+        int start = 1;
+        int end = 100000;
+        int batch = (end-start+1)/(threadsNum-1);
+
+        Thread[] threads = new Thread[threadsNum];
+        RunnablePrimeFinder[] runnables = new RunnablePrimeFinder[threadsNum-1];
+
+        for(int i = 0; i<threadsNum-1; i++)
+        {
+            runnables[i] = new RunnablePrimeFinder((i)*batch +1,batch * (i+1));
+            threads[i] = new Thread(runnables[i]);
+            threads[i].start();
+        }
+
+        threads[threadsNum-1] = new Thread(()->
+        {
+            for(int i = 0; i<threadsNum-1;i++)
+            {
+                try
+                {
+                    threads[i].join();
+                }
+                catch (InterruptedException e)
+                {
+                    throw new RuntimeException(e);
+                }
+            }
+
+            for(int i = 0;i<threadsNum-1;i++)
+            {
+                System.out.println("Prime numbers in thread " + (i + 1) + ": " + runnables[i].getPrimeNumbers());
+            }
+        });
+
+        threads[threadsNum-1].start();
+
+
+
+        long endTime = System.nanoTime();
+        long executionTime = endTime - startTime;
+
+        System.out.println("Execution time: " + executionTime + " nanoseconds");
+        System.out.println("Execution time: " + (executionTime / 1_000_000) + " milliseconds");
+    }
+}
+
+class RunnablePrimeFinder implements Runnable
+{
+    private int start;
+    private int end;
+    private List<Integer> primeNumbers;
+
+    public RunnablePrimeFinder(int s, int e)
+    {
+        start = s;
+        end = e;
+        primeNumbers = new ArrayList<Integer>();
+    }
+
+    @Override
+    public void run()
+    {
+        for(int i = start; i<=end; i++)
+        {
+            if(isPrime(i))
+            {
+                primeNumbers.add(i);
+            }
+        }
+
+    }
+
+    private boolean isPrime(int n)
+    {
+        if (n <= 1) {
+            return false;
+        }
+        if (n <= 3) {
+            return true;
+        }
+        if (n % 2 == 0 || n % 3 == 0) {
+            return false;
+        }
+        for (int i = 5; i * i <= n; i += 6) {
+            if (n % i == 0 || n % (i + 2) == 0) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public List<Integer> getPrimeNumbers()
+    {
+        return primeNumbers;
+    }
+}