java读取文件——1

题目：租用游艇问题

先解决文件的读入，主要是将文件中数据转换成类似上三角矩阵：

0 13 15 24 44
0 0 16 18 8
0 0 0 7 26
0 0 0 0 12
0 0 0 0 0

public void inputfile()  {
        FileInputStream fileInputStream = null;
        try {
            fileInputStream = new FileInputStream("boat2.txt");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
        Scanner scanner =new Scanner(fileInputStream);
        int n=scanner.nextInt();
        int[][] r=new int[n][n];
        for (int i = 0; i < n-1; i++) {
            for (int j = i+1; j <n; j++) {
                r[i][j]=scanner.nextInt();
            }
        }
        MyUtil.printM(r, 0, 5)；

    }

　　

 

了解到scanner类 里面的next()方法和hasnext() 方法：

上大佬文章

https://blog.csdn.net/qq_41115971/article/details/110820678?ops_request_misc=%257B%2522request%255Fid%2522%253A%2522164931306316780357283196%2522%252C%2522scm%2522%253A%252220140713.130102334..%2522%257D&request_id=164931306316780357283196&biz_id=0&utm_medium=distribute.pc_search_result.none-task-blog-2~all~top_click~default-2-110820678.142^v5^pc_search_result_control_group,157^v4^control&utm_term=hasNext&spm=1018.2226.3001.4187