# Solving Leetcode Interviews in Seconds with AI: Excel Sheet Column Number


	# Introduction
	In this blog post, we will explore how to solve the LeetCode problem "171" using AI. LeetCode is a popular platform for preparing for coding interviews, and with the help of AI tools like [Chatmagic](https://www.chatmagic.app), we can generate solutions quickly and efficiently - helping you pass the interviews and get the job offer without having to study for months.

	# Problem Statement
	> Given a string columnTitle that represents the column title as appears 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: columnTitle = "A" Output: 1  Example 2:  Input: columnTitle = "AB" Output: 28  Example 3:  Input: columnTitle = "ZY" Output: 701    Constraints:  1 <= columnTitle.length <= 7 columnTitle consists only of uppercase English letters. columnTitle is in the range ["A", "FXSHRXW"].  

	# Explanation
	*   The core idea is to treat the column title as a base-26 number, where 'A' represents 1, 'B' represents 2, and so on, up to 'Z' representing 26.
*   Iterate through the string from left to right, updating the result by multiplying the current result by 26 and adding the value of the current character.
*   The value of each character is determined by its position relative to 'A' in the alphabet.

*   **Runtime Complexity:** O(n), where n is the length of the column title. **Storage Complexity:** O(1).

	
	# Code
	```python
	class Solution:
    def titleToNumber(self, columnTitle: str) -> int:
        result = 0
        for char in columnTitle:
            result = result * 26 + (ord(char) - ord('A') + 1)
        return result
	```