题解 | #在字符串中找出连续最长的数字串#

class HelloWorld {
    public static void main(String[] args) {
      Scanner in = new Scanner(System.in);
       String s = in.nextLine();
      StringBuilder sb = new StringBuilder();
        int c = 0;
        int res = 0;
      //第一次遍历先找到最长的数字串长度
      //
        for (int i = 0; i < s.length(); i++) {
            if (Character.isDigit(s.charAt(i))) {
                c++;
            } else {
                res = Math.max(c, res);
                c = 0;
            }
        }
        res = Math.max(c, res);
        c = 0;
        int start = 0, end = 0;
      // 第二次遍历 遇到数字和最长的比较等于就拼接
        for (int i = 0; i < s.length(); i++) {
            if (Character.isDigit(s.charAt(i))) {
                c++;
                start = i;
                end = i;
                while (end < s.length() && Character.isDigit(s.charAt(end))) {
                    end++;
                }
                if ((end - start) == res) {
                    sb.append(s.substring(start, end));
                } else {
                    i = end - 1;
                }
            }
        }

        System.out.println(sb.toString() + "," + res);
    }
}