import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Paths;
import static java.util.Arrays.stream;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Main {

    public static void main(String[] args) {
        System.out.println("Maximum Sum : " + findSum("file.txt"));
    }

    
    public static int findSum(String filename) {
        // Get triangle array from file
        int[][] numbers = null;
        try {
            numbers = Files.lines(Paths.get(filename)).map(s -> stream(s.trim().split("\\s+")).mapToInt(Integer::parseInt).toArray()).toArray(int[][]::new);
        } catch (IOException ex) {
            Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
        }
        
        // Write triangle array
        for (int i = 0; i < numbers.length; i++) {
            for (int j = 0; j < numbers[i].length; j++) {
                System.out.printf(numbers[i][j] + " ");
            }
            System.out.printf("\n");
        }
     
        // Get maximum sum with controls
        int sum = 0; 
        for (int rowIndex = numbers.length - 1; rowIndex > 0; rowIndex--) {
            for (int columnIndex = 0; columnIndex < numbers[rowIndex].length - 1; columnIndex++) {
                if (!isPrime(numbers[rowIndex - 1][columnIndex]) || (rowIndex == 1)) {
                    if (rowIndex == numbers.length - 1) {
                        int max = Math.max(isPrime(numbers[rowIndex][columnIndex]) ? 0 : numbers[rowIndex][columnIndex],
                                isPrime(numbers[rowIndex][columnIndex + 1]) ? 0 : numbers[rowIndex][columnIndex + 1]);
                        
                        numbers[rowIndex - 1][columnIndex] += max;
                    } else {
                        int max = Math.max(numbers[rowIndex][columnIndex], numbers[rowIndex][columnIndex + 1]);
                        
                        numbers[rowIndex - 1][columnIndex] += max;
                    }
                    sum = numbers[rowIndex - 1][columnIndex];
                } else { // If it is prime number
                    numbers[rowIndex - 1][columnIndex] = 0;
                    sum = numbers[rowIndex - 1][columnIndex];
                }

            }         
        }
        
        return sum;
    }
    
    
    // A function which we can get 'true' if given number is prime
    public static boolean isPrime(int number) {
        if (number <= 1) {
             return false;
        }
        for (int i = 2; i <= Math.sqrt(number); i++) {
            if (number % i == 0) {
                return false;
            }
        }
         return true;
    }
    
}