题解 | #密码验证合格程序#

import java.util.*;
import java.util.regex.*;
public class Main{
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        while (in.hasNextLine()) {
            String input = in.nextLine();
            boolean regex = checkRegex(input);
            boolean duplicate = checkDuplicate(input);
            if (input.length() > 8 && regex && duplicate) {
                System.out.println("OK");
            } else {
                System.out.println("NG");
            }
        }
    }

    private static boolean checkDuplicate(String str) {
        int dupIndex = str.length() / 2;
        for (int i = 0; i <= dupIndex; i++) {
            for (int j = i + 3; j <= dupIndex; j++) {
                String substring = str.substring(i, j);
                String otherString = str.substring(j);
                if (otherString.contains(substring)) {
                    return false;
                }
            }
        }
        return true;
    }

    static boolean checkRegex(String input) {
        int count = 0;
        Pattern upperLetter = Pattern.compile("[A-Z]+");
        Pattern lowerLetter = Pattern.compile("[a-z]+");
        Pattern number = Pattern.compile("\\d+");
        Pattern others = Pattern.compile("[^a-zA-Z0-9]");

        if (upperLetter.matcher(input).find()) {
            count++;
        }
        if (lowerLetter.matcher(input).find()) {
            count++;
        }
        if (number.matcher(input).find()) {
            count++;
        }
        if (others.matcher(input).find()) {
            count++;
        }

        if (count < 3) {
            return false;
        }
        return true;
    }
}