LeetCode168. Excel Sheet Column Title

文章目录

• • 一、题目
  • 二、题解

一、题目

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

二、题解

class Solution {
public:
    string convertToTitle(int columnNumber) {
        string res;
        while (columnNumber > 0) {
            int a0 = (columnNumber - 1) % 26 + 1;
            res += a0 - 1 + 'A';
            columnNumber = (columnNumber - a0) / 26;
        }
        reverse(res.begin(), res.end());
        return res;
    }
};