LeetCode - Excel Sheet Column Number

https://leetcode.com/problems/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 

这道题跟前一道题是对应的，这里更简单，就是求出每一位对应的值，然后按26进制算就行了。

    public int titleToNumber(String s) {
        int val = 0;
        for(int i=0; i<s.length(); i++){
            int current = s.charAt(i) - 'A'+1;
            val = val*26+current;
        }
        return val;
    }