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
...
Example 1:Input: "A"
Output: 1
Example 2:Input: "AB"
Output: 28
Example 3:Input: "ZY"
Output: 701
class Solution {
public int titleToNumber(String s) {
int result = 0;
for (int i = 0; i < s.length(); i++)
{
result *= 26;
result += s.charAt(i) - 'A' + 1;
}
return result;
}
}