笔试算法《密码验证合格程序》

题目描述

• 密码要求:
• 1.长度超过8位
  2.包括大小写字母.数字.其它符号,以上四种至少三种
  3.不能有相同长度大于2的子串重复
• 输入描述:
  一组或多组长度超过2的字符串。每组占一行
• 输出描述:
  如果符合要求输出：OK，否则输出NG
• 示例1
  输入
  021Abc9000
  021Abc9Abc1
  021ABC9000
  021$bc9000
• 输出
  OK
  NG
  NG
  OK

代码

public class Huawei密码验证合格程序 {

    public static void main(String[] args) throws IOException {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String str;
        StringBuffer sb = new StringBuffer();
        while (!(str = reader.readLine()).equals("")) {
            String result = "OK";
            //长度超过8位
            if (str.length() < 9) {
                result = "NG";
            } else {
                char[] chars = str.toCharArray();
                int a = 0, A = 0, n = 0, c = 0;
                //至少三种类型
                for (int i = 0; i < chars.length; i++) {
                    if (chars[i] >= 'a' && chars[i] <= 'z') {
                        a = 1;
                    } else if (chars[i] >= 'A' && chars[i] <= 'Z') {
                        A = 1;
                    } else if (chars[i] >= '0' && chars[i] <= '9') {
                        n = 1;
                    } else {
                        c = 1;
                    }
                    //不能有相同长度大于2的子串重复
                    if (i + 2 + 3 < chars.length) {
                        for (int j = i + 3; j < chars.length - 2; j++) {
                            if (chars[i] == chars[j] && chars[i + 1] == chars[j + 1] && chars[i + 2] == chars[j + 2]) {
                                result = "NG";
                                break;
                            }
                        }
                    }
                }
                if (a + A + n + c < 3) {
                    result = "NG";
                }
            }
            sb.append(result).append("\n");
        }
        System.out.println(sb.toString());

    }