题解 | #密码验证合格程序#

// mark一下啦
// 重点在于理解题意 重复字串

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        while (in.hasNextLine()) { 
            String s = in.nextLine();
            int length = s.length();
            if (length <= 8) {
                System.out.println("NG");
                continue;
            }
            
            int lowerCaseNum = 0;
            int upperCaseNum = 0;
            int digitNum = 0;
            int otherNum = 0;
            for (int i = 0; i < length; i++) {
                char c = s.charAt(i);
                if (c >= 'a' && c <= 'z') {
                    lowerCaseNum++;
                } else if (c >= 'A' && c <= 'Z') {
                    upperCaseNum++;
                } else if (c >= '0' && c <= '9') {
                    digitNum++;
                } else {
                    otherNum++;
                }
            }

            lowerCaseNum = lowerCaseNum > 0 ? 1 : 0;
            upperCaseNum = upperCaseNum > 0 ? 1 : 0;
            digitNum = digitNum > 0 ? 1 : 0;
            otherNum = otherNum > 0 ? 1 : 0;
            int allNum = lowerCaseNum + upperCaseNum + digitNum + otherNum;
            if (allNum < 3) {
                System.out.println("NG");
                continue;
            }

            boolean valid = true;
            for (int i = 0 ; i < length - 3; i++) {
                int j = i + 3;
                String substr = s.substring(i, j);
                if (s.indexOf(substr) != s.lastIndexOf(substr)) {
                    valid = false;
                    System.out.println("NG");
                    break;
                }
            }
            if (!valid) {
                continue;
            }

            System.out.println("OK");
        }
    }
}