Is Excel Sheet Column Title easy or hard?

Excel Sheet Column Title is classified as an Easy problem. The main challenge is recognizing the 1‑indexed base‑26 system used by Excel columns. Once the (n - 1) adjustment is understood, the implementation becomes straightforward.

Excel Sheet Column Title Python/Java solution

Python, Java, C++, C#, and JavaScript implementations all follow the same logic: repeatedly compute (n - 1) % 26 to get the current letter and divide the number by 26. The difference is only in syntax for string building and character conversion.

How to solve Excel Sheet Column Title in O(log n)?

Use a modified base‑26 conversion. Decrement the column number before applying modulo: remainder = (n - 1) % 26. Convert the remainder to a character using 'A' + remainder, append it to the result, then update n = (n - 1) / 26. Repeat until n becomes zero and reverse the string at the end.

What is the best approach for Excel Sheet Column Title?

The base‑26 conversion approach is the most efficient and widely expected solution. Repeatedly compute (n - 1) % 26 to determine the current character and divide the number by 26 to move to the next position. This handles Excel’s 1‑indexed alphabet mapping correctly. The algorithm runs in O(log n) time and O(1) extra space.

Is Excel Sheet Column Title asked at Google/Amazon/Meta?

This problem appears frequently in coding interviews at companies that emphasize basic algorithmic reasoning, including Amazon and Microsoft. It tests understanding of number systems, edge cases in indexing, and careful handling of modulo arithmetic.

What data structure is used in Excel Sheet Column Title?

The solution mainly uses arithmetic operations and string construction. No complex data structure is required. A simple string builder or character array is enough to accumulate characters during the base‑26 conversion process.

What is the time complexity of Excel Sheet Column Title?

The time complexity is O(log26 n), commonly written as O(log n). Each iteration extracts one character of the resulting Excel column title, reducing the number by a factor of 26. Since the number of characters in the output grows logarithmically with the input value, the algorithm scales efficiently.

Description Solution Video 14:37

168. Excel Sheet Column Title

Easy47.9% acceptance10 companies

Given an integer columnNumber, return its corresponding column title as it appears in an Excel sheet.

For example:

A -> 1
B -> 2
C -> 3
...
Z -> 26
AA -> 27
AB -> 28 
...

Example 1:

Input: columnNumber = 1
Output: "A"

Example 2:

Input: columnNumber = 28
Output: "AB"

Example 3:

Input: columnNumber = 701
Output: "ZY"

Constraints:

1 <= columnNumber <= 2³¹ - 1

Asked at 10 companies

Zenefits Ola Microsoft Zoho D. E. Shaw

Google Amazon Meta Accenture Bloomberg

Topics

Math String

14:37

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168. Excel Sheet Column Title

Asked at 10 companies

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