笔试题讨论一下,该怎么处理

笔试题讨论一下
昨天晚上参加baidu笔试的2个题目，大家讨论一下：

1.序列Seq=[a,b,…z,aa,ab…az,ba,bb,…bz,…,za,zb,…zz,aaa,…] 类似与excel的排列，任意给出一个字符串s=[a-z]+(由a-z字符组成的任意长度字符串），请问s是序列Seq的第几个。

2.需求：需要引入用户对搜索结果相关性的评分100分制，希望用户的打分能帮助搜索引擎排序，但又要避免恶意投票，作弊等，请设计一个比较公平的评分系统。

[解决办法]
第一题，相当于26进制嘛，
[解决办法]

Java code

public class Test1 {        public static void main(String[] args) {        int n = letter2Number("abc");        System.out.println(n);    }        public static int letter2Number(String letters) {        if(!letters.matches("[a-zA-Z]+")) {            throw new IllegalArgumentException("Format ERROR!");        }        char[] chs = letters.toLowerCase().toCharArray();         int result = 0;        for(int i = chs.length - 1, p = 1; i &gt;= 0; i--) {                        result += getNum(chs[i]) * p;            p *= 26;        }        return result;    }        private static int getNum(char c) {        return c - 'a' + 1;    }}
[解决办法]
Java codeString str = "abcdefghijklmnopqrstuvwxyz";     public int getNum(String oneChar){//传一个字母         return str.indexOf(oneChar)+1;     }     public int q26(int a){        if(a==0){            return 1;        }        else if(a==1){            return 26;        }        else{            return 26*q26(a-1);        }    }    public int changeToNum(String moreChar){//传的是一个字符串         int all = 0;         int p = 0;        char[] newOne = moreChar.toCharArray();         //挨个字母换成十进制数，然后再运算         for(int i = 0 ;i &lt;newOne.length ; i++){             String tag = Character.toString(newOne[i]);            int num = getNum(tag);            all = all + num*q26(newOne.length-i-1);        }         return all;     }
[解决办法]
那么麻烦?

JDK里面就有了,一句话:

ava.lang.Integer.parseInt(String "abc", 26);



int java.lang.Integer.parseInt(String s, int radix) throws NumberFormatException
Parses the string argument as a signed integer in the radix specified by the second argument. The characters in the string must all be digits of the specified radix (as determined by whether java.lang.Character.digit(char, int) returns a nonnegative value), except that the first character may be an ASCII minus sign '-' ('\u002D') to indicate a negative value. The resulting integer value is returned.  

An exception of type NumberFormatException is thrown if any of the following situations occurs:  

The first argument is null or is a string of length zero.  
The radix is either smaller than java.lang.Character.MIN_RADIX or larger than java.lang.Character.MAX_RADIX.  
Any character of the string is not a digit of the specified radix, except that the first character may be a minus sign '-' ('\u002D') provided that the string is longer than length 1.  
The value represented by the string is not a value of type int.  
Examples:  

  parseInt("0", 10) returns 0
  parseInt("473", 10) returns 473
  parseInt("-0", 10) returns 0
  parseInt("-FF", 16) returns -255
  parseInt("1100110", 2) returns 102
  parseInt("2147483647", 10) returns 2147483647
  parseInt("-2147483648", 10) returns -2147483648
  parseInt("2147483648", 10) throws a NumberFormatException
  parseInt("99", 8) throws a NumberFormatException
  parseInt("Kona", 10) throws a NumberFormatException
  parseInt("Kona", 27) returns 411787 
 
  
Parameters:
s the String containing the integer representation to be parsed
radix the radix to be used while parsing s.
Returns:
the integer represented by the string argument in the specified radix.
Throws:
NumberFormatException if the String does not contain a parsable int.
[解决办法]
第二题有一个大概是思路，根据投票排序就不用说了。在防恶意投票方面可以做一个反恶意作弊规则，比如：投票者所给的分数越接近经过统计求值后的本搜索结果分数就会得到越高的分数，这样在一定程度上可以防止恶意评分。反作弊的话，就规定每个用户只可以评分一次就可以了。

笔试题 讨论一下,该怎么处理

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笔试题讨论一下,该怎么处理