LeetCode171: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 

int titleToNumber(char* s) {
    int result=0;
    int i=0;
    while(i<strlen(s))
    {
        result=result*26+(s[i]-'A'+1);
        i++;
    }
    return result;
}