密码验证

题目要求

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.不能有相同长度超2的子串重复       说明:长度超过2的子串

输入例子:

021Abc9000 021Abc9Abc1 021ABC9000 021$bc9000

输出例子:

OK NG NG OK

import java.util.Scanner;

 

/**

 * Author: 王俊超

 * Date: 2015/12/22 15:45

 * All Rights Reserved !!!

 */

public class Main {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);

//        Scanner scanner = new Scanner(Main.class.getClassLoader().getResourceAsStream("data.txt"));

        StringBuilder builder = new StringBuilder();

        while (scanner.hasNext()) {

            String input = scanner.nextLine();

            System.out.println(passwordValidate(input));

        }

        scanner.close();

 

    }

 

    private static String passwordValidate(String input) {

        final String OK = "OK";

        final String NG = "NG";

 

        // 长度超过8

        if (input == null || input.length() < 9) {

            return NG;

        }

 

        int[] kind = new int[4];

 

        // 统计

        for (int i = 0; i < input.length(); i++) {

            char ch = input.charAt(i);

            if (ch >= 'A' && ch <= 'Z') {

                kind[0] |= 1;

            } else if (ch >= 'a' && ch <= 'z') {

                kind[1] |= 1;

            } else if (ch >= '0' && ch <= '9') {

                kind[2] |= 1;

            } else {

                kind[3] |= 1;

            }

        }

         

        // 小于三种

        if ((kind[0] + kind[1] + kind[2] + kind[3]) < 3) {

            return NG;

        }

 

        for (int i = 0; i < input.length() - 3; i++) {           //因为超过2即最小是三


            String s1 = input.substring(i, i + 3);              // 吧字符串分隔，看后面的是否包含前面的即可


            String s2 = input.substring(i + 3, input.length());

            if (s2.contains(s1)) {

                return NG;

            }

        }

        return OK;

    }

}

 

 

字符串截取,substring(int beginIndex) 返回一个新的字符串，它是此字符串的一个子字符串。
substring(int beginIndex, int endIndex) 返回一个新字符串，它是此字符串的一个子字符串。       //即subString是左闭右开的
beginIndex - 起始索引（包括）。从0开始
endIndex - 结束索引（不包括）。
"unhappy".substring(2) returns "happy"
"hamburger".substring(4, 8) returns "urge"