class MyThread extends Thread {
                private int start, end;
                private int sum = 0;
                
                MyThread(int start, int end) {
                this.start = start;
                this.end = end;
                }
                
                public void run() {
                System.out.println("My thread is running");
                for (int i = start; i <= end; i++) {
                if (isPrime(i))
                sum += i;
                }
                }
                
                boolean isPrime(int n) {
                if (n == 0 || n == 1)
                return false;
                for (int i = 2; i <= Math.sqrt(n); ++i) {
                if (n % i == 0)
                return false;
                }
                return true;
                }
                
                public int getSum() {
                return sum;
                }
                }
                
                class program5 {
                MyThread[] myThreads;
                private int sum = 0;
                private int limit = 20;
                private static int threadCount = 4;
                
                // Constructor to initialize the array of threads
                public program5(int n) throws InterruptedException {
                this.myThreads = new MyThread[n];
                for (int i = 0; i < n; i++) {
                int start = ((limit * i) / n);
                int end = (i == n-1) ? limit : ((limit * (i+1))/n) - 1;
                myThreads[i] = new MyThread(start, end);
                }
                }
                
                // Function to start all threads
                public void startAll() throws InterruptedException {
                for (int i = 0; i < myThreads.length; i++) {
                myThreads[i].start();
                myThreads[i].join();
                }
                }
                
                public void getSum() {
                for (int i = 0; i < myThreads.length; i++) {
                this.sum += myThreads[i].getSum();
                }
                }
                
                public static void main(String[] args) {
                try {
                program5 mt = new program5(threadCount);
                mt.startAll();
                mt.getSum();
                System.out.println("Sum of prime numbers is " + mt.sum);
                } catch (InterruptedException e) {
                System.err.print("Error: " + e);
                }
                }
                }