java问题求，含k个3的数

网址;

OpenJudge - 30:含k个3的数 http://noi.openjudge.cn/ch0105/30/

```java
public static void main(String[] args) {
  Scanner in = new Scanner(System.in);
  String s = in.nextLine();
  String[] strs = s.split(" ");
  if (strs.length != 2) {
    System.out.println("输入非法");
  }
  try {
    String aStr = strs[0];
    int a = Integer.valueOf(aStr);
    int b = Integer.valueOf(strs[1]);
    boolean flag = false;
    if (a % 19 == 0) {
      int index = 0, count = 0;
      while ((index = aStr.indexOf("3", index)) != -1) {
        index = index + 1;// 1是字符"3"的长度
        count++;
      }
      if (count == b) {
        flag = true;
      }
    }
    if (flag) {
      System.out.println("YES");
    } else {
      System.out.println("NO");
    }
  } catch (Exception e) {
    System.out.println("输入非法");
  }
}

```

Scanner s = new Scanner(System.in);
        int m = s.nextInt();
        int k = s.nextInt();
        int l = 0;
        String m1 = String.valueOf(m);
        if (m%19==0) {
            for (int i = 0; i < m1.length(); i++) {
                if(m1.charAt(i) == '3') {
                    l++;
                }
            }
            if (l == k) {
                System.out.println("YES");
            }else {
                System.out.println("NO");
            }
        }else {
            System.out.println("NO");
        }