1740 : 소수

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.util.StringTokenizer;
 
public class Main {
 
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
        BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
        BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out));
     
        int n, m;
        int i, j;
         
        n = Integer.parseInt(in.readLine());
        m = Integer.parseInt(in.readLine());
     
        int sum = 0;
        int min = 0;
        int flag = 0;
         
        for (i = n; i <= m; i++) {
            if (isPrime(i)) {
                if (flag == 0) {
                    min = i;
                    flag = 1;
                }
                sum = sum + i;
            }
        }
         
        if (flag == 0) {
            bw.write("-1");
        }
        else {
            bw.write(String.format("%d\n", sum));
            bw.write(String.format("%d\n", min));
        }
        bw.flush();
    }
     
    public static boolean isPrime(int num) {
        if(num<2) return false;
        for(int i=2;i<=Math.sqrt(num);i++) {
            if(num%i==0) return false;
        }
        return true;
    }
 
}

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