LeetCode 171 Excel Sheet Column Number

相当于26进制

class Solution {public:    int titleToNumber(string s) {        int t = 1;        int ans = 0;        for (int i = s.size() - 1; i >= 0; i--) {            ans += t * (s[i] - 'A' + 1);            t *= 26;        }        return ans;    }};