View Code of Problem 27

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scanner=new Scanner(System.in);
		while(scanner.hasNext()) {
			long a=scanner.nextLong();
			long b=scanner.nextLong();
			long sum=0;
			if(a>b) {
				long t=a;
				a=b;
				b=t;
			}
			for(long i=a+1;i<b;i++) {
				boolean flag=true;
				for(int j=2;j<=Math.sqrt(i);j++) {
					if(i%j==0) {
						flag=false;
						break;
					}
				}
				if(i==1) {
					break;
				}
				if(flag) {
					sum+=i;
				}
			}
			System.out.println(sum);
		}
	}

}