1. 题目

读题

 HJ90 合法IP

考查点

2. 解法

思路

代码逻辑

具体实现

自行实现

public class HJ090 {

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        System.out.println(isValid(sc.nextLine()) ? "YES" : "NO");
    }

    public static boolean isValid(String ip) {
        String[] segments = ip.split("\\.");
        if (segments.length != 4) {
            return false;
        }

        for (String segment : segments) {
            if (segment.length() == 0) {
                return false;
            }
            for (char ch : segment.toCharArray()) {
                if (!Character.isDigit(ch)) {
                    return false;
                }
            }
            if (segment.length() > 1 && segment.charAt(0) == '0' || Integer.parseInt(segment) > 255 || Integer.parseInt(segment) < 0) {
                return false;
            }
        }
        return true;

    }
}

3. 总结