Problem:
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
A possible answer:
class Solution {
public:
int titleToNumber(string s) {
int res=0;
for(int i=0;i<s.size();i++)
{
res = res*26+ s[i]-'A'+1;
}
return res;
}
};