[LeetCode] Excel Sheet Column Number

Excel Sheet Column Number

Related to question Excel Sheet Column Title

Given a column title as appear in an Excel sheet, return its corresponding column number.

For example:

    A -> 1    B -> 2    C -> 3    ...    Z -> 26    AA -> 27    AB -> 28 

解题思路：

看成是进制转化的问题，这个是26进制转化成10进制。比较简单，代码如下：

class Solution {public:    int titleToNumber(string s) {        int len=s.length();        if(len==0){            return 0;        }        int result = 0;        for(int i=0; i<len; i++){            result *= 26;            result += s[i] - 'A' + 1;        }        return result;    }};