maximum matrix sum dfs

maximummatrixsumdfs.java

// java.util.* and java.util.streams.* have been imported for this problem.
// You don't need any other imports.

public static int matrixMaxSumDfs(int[][] grid) {
    
    int[] sum = new int[1];
    int answer = helper(grid, 0, 0, sum);
    return answer;
}


private static int helper(int [][] matrix, int a, int b, int[] sum) {
    
    int rows = matrix.length;
    int cols = matrix[0].length;
    
    if(a == rows || b==cols) {
        return 0;
    }
    
    if(a==rows-1 && b==cols-1) {
        return matrix[a][b];
    }
  
    
    int down = helper(matrix, a+1, b, sum);
    
    
    int right = helper(matrix, a, b+1, sum);
        
    if (down + matrix[a][b] > right + matrix[a][b]) {
        return down + matrix[a][b];
    }
    return right + matrix[a][b];
}