171. 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.

link to 168 Excel Sheet Column Title

For example:

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

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