LeetCode -- Excel Sheet Column Number

public class Solution {
    public int TitleToNumber(string s) 
    {
    	var sum = 0;
    	for(var i = s.Length - 1; i >= 0; i--){
    		var d = s.Length - i;
    		var n = Num(s[i]);
    		sum += (int)Math.Pow(26, d-1) * n;
    	}
    	return sum;
    }
	
private int Num(char c)
{
	return (int)c - 64;
}


}

LeetCode -- Excel Sheet Column Number

原文：http://blog.csdn.net/lan_liang/article/details/48575959