Java对数组进行排序

class Solution {
    class Node{
        int val;
        int row;
        int col;
        public Node(int row,int col,int val){
            this.val = val;
            this.row = row;
            this.col = col;
        }
    }
    public int[][] matrixRankTransform(int[][] matrix) {
        int m = matrix.length;//矩阵的行
        int n = matrix[0].length;//矩阵的列
        int[] rowRank = new int[m];//行的当前的秩
        int[] colRank = new int[n];//列的当前秩
        Node[] nodes = new Node[m*n];
        int[][] ans = new int[m][n];
        int index = 0;
        for(int i = 0;i < m;i++){//根据matrix创建node
            for(int j = 0;j < n;j++){
               nodes[index++] = new Node(i,j,matrix[i][j]);
            }
        }
        Arrays.sort(nodes, new Comparator(){ //对Node数组进行排序
            public int compare(Node n1,Node n2){//按node.val进行升序排序
                return n1.val - n2.val;
        }});
        System.out.println(nodes[0].val);
        System.out.println(nodes[1].val);
        return ans;
    }
}