我有一个个人编码问题。我正在尝试在Java中使用前驱矩阵编写Floyd-Warshall算法的代码。我的目标是同时返回我不知道该怎么做的矩阵数组和predMatrix，并且当我只返回一个矩阵矩阵来运行它时，在java.util.ArrayList上我得到了indexoutOfboundsException：-1。 java.util.ArrayList.get处的elementData（未知来源）（未知来源）

public int[][] floydWarshall(Graph g) {     
    ArrayList<Edge> n = g.getEdgeList();

    int[][] matrix = new int[n.size()][n.size()];
    int[][] predMatrix = new int[0][0];
    for(int k = 0; k <= n.size(); k++) {
        for(int i = 0; i < n.size(); i++) {
            for(int j = 0; j < n.size(); j++) {
                String label = n.get(k - 1).getLabel();
                String label2 = n.get(i).getLabel();
                String label3 = n.get(j).getLabel();
                //String predessor = n.get(k).getTail().getName();
                int kDistance = Integer.parseInt(label);
                int iDistance = Integer.parseInt(label2);
                int jDistance = Integer.parseInt(label3);
                if((matrix[iDistance][jDistance] == Integer.MAX_VALUE) &&
                        (matrix[iDistance][kDistance] + matrix[kDistance][jDistance] == Integer.MAX_VALUE)) {
                        continue;
                    //matrix[iDistance][jDistance] = kDistance;
                } else if(matrix[iDistance][jDistance] <= matrix[iDistance][kDistance] + matrix[kDistance][jDistance])
                    matrix[iDistance][jDistance] = matrix[iDistance][jDistance];
                    predMatrix[iDistance][jDistance] = predMatrix[iDistance][jDistance];
                }else {
                    matrix[iDistance][jDistance] = matrix[iDistance][kDistance] + matrix[kDistance][jDistance];
                    predMatrix[iDistance][jDistance] = predMatrix[kDistance][jDistance];

                }
            }
        }
    }
    return matrix;
}