Excel Sheet Column Number Problem & Solution
Given a string columnTitle that represents the column title as appears in an Excel sheet, return its corresponding column number.
See the Excel sheet column number problem on LeetCode.
C++ Solution
#pragma GCC optimize("Ofast")
#pragma GCC optimization("unroll-loops")
static const int _=[](){std::ios::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);return 0;}();
class Solution {
public:
int titleToNumber(string columnTitle) {
int result = 0;
for (int i = 0; i < columnTitle.size(); ++i) {
// The parentheses to calculate the digits are used to avoid overflow.
result = result * 26 + (columnTitle[i] - 'A' + 1);
}
return result;
}
};