[LeetCode] 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 

/*****************************************************************************
    *  @COPYRIGHT NOTICE
    *  @Copyright (c) 2015, 楚兴
    *  @All rights reserved
    *  @Version  : 1.0

    *  @Author   : 楚兴
    *  @Date     : 2015/2/6 14:29
    *  @Status   : Accepted
    *  @Runtime  : 15 ms
*****************************************************************************/
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
class Solution {
public:
	int titleToNumber(string s) {
		int column = 0;
		for (int i = 0; i < s.size(); i++)
		{
			if (s[i] >= 'A' && s[i] <= 'Z')
			{
				column = column * 26 + s[i] - 'A' + 1;
			}
		}
		return column;
	}
};
int main()
{
	Solution s;
	int a = s.titleToNumber("AA");
	cout<<a<<endl;
	system("pause");
}