Solution.java

/**
 * @author Oleg Cherednik
 * @since 19.02.2020
 */
public class Solution {

    public static void main(String... args) {
        System.out.println(findMaxWeightPath(new int[][] { { 1 }, { 2, 3 }, { 1, 5, 1 } })); // 9
    }

    public static int findMaxWeightPath(int[][] arr) {
        int res = 0;

        for (int row = 0; row < arr.length; row++) {
            for (int col = 0; col < arr[row].length; col++) {
                arr[row][col] += Math.max(left(arr, row, col), right(arr, row, col));
                res = Math.max(res, arr[row][col]);
            }
        }

        return res;
    }

    private static int left(int[][] arr, int row, int col) {
        return row == 0 || col == 0 ? 0 : arr[row - 1][col - 1];
    }

    private static int right(int[][] arr, int row, int col) {
        return row == 0 || col == arr[row].length - 1 ? 0 : arr[row - 1][col];
    }

}