程序在做什么

Question

这个程序是找不到的。可被k整除的输入。
但是我得到了一个执行此操作的程序，但无法理解标记为// <--的代码是什么。

public static void main(String[] args) throws NumberFormatException, IOException {
    BufferedReader br = new BufferedReader(new InputStreamReader (System.in));

    String s = br.readLine();// <--
    int end = s.indexOf(' ');// <--
    int n = Integer.parseInt(s.substring(0, end));// <--
    int k = Integer.parseInt(s.substring(end+1));// <--

    int count = 0;

    for (int i=0; i < n; i++){
        if (Integer.parseInt(br.readLine())%k == 0){
            count++;
        }
    }
    System.out.println(count);  
}

Answer 1

用注释解释代码：

public class division {
    public static void main(String[] args) throws NumberFormatException, IOException {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

        String s = br.readLine(); //reads a line from the console (user has to enter with keyboard and then push [ENTER])
        int end = s.indexOf(' '); //finds the index of the first space and writes it into "end"
        int n = Integer.parseInt(s.substring(0, end)); //parses an int from the given user input. stops at the first space (because of "end")
        int k = Integer.parseInt(s.substring(end + 1)); //parses an int from the given user input. starts after the first space (because of "end")

        int count = 0;

        for (int i = 0; i < n; i++) {
            if (Integer.parseInt(br.readLine()) % k == 0) {
                count++;
            }
        }
        System.out.println(count);
    }
}

演示输入：

1. 编译并运行程序
2. 输入以下字符串3 4，然后按[ENTER]（第一个数字确定您进行检查的频率，第二个数字确定您要检查的数字）
3. 输入以下字符串8 12 7，然后按[ENTER]（这些是您要检查的数字）
4. 您在控制台2中得到结果（因为两个数字（8＆amp; 12）可被4整除）

Answer 2

 String s = br.readLine();// reads the inputstream

    int end = s.indexOf(' '); //make a integer variable and initialize it with the index of  first space in string
    int n = Integer.parseInt(s.substring(0, end)); // performs substring operation and this line stops at the first space 
    int k = Integer.parseInt(s.substring(end+1));*/ performs substring operation and stops at after the first space

Answer 3

在运行程序时，您必须通过＆＃34; n＆＃34;和＆＃34; k＆＃34;由控制台上的（＆＃34;＆＃34;）空格分隔。 你的程序做的是它从控制台作为一个完整的字符串。 现在，您的注释代码将拆分此字符串并将其解析为整数。

也可以实现这一目标

String[] nums = br.readLine().split(" ");
int n = Integer.parseInt(nums[0]);
int k = Integer.parseInt(nums[1]);