168. Excel Sheet Column Title

• Difficulty: Easy

• Topics: Math

• Similar Questions:

  • Excel Sheet Column Number

Problem:

Given a positive integer, return its corresponding column title as appear in an Excel sheet.

For example:

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

Example 1:

Input: 1
Output: "A"

Example 2:

Input: 28
Output: "AB"

Example 3:

Input: 701
Output: "ZY"

Solutions:

class Solution {
public:
    string convertToTitle(int n) {
        string ret;
        while (n > 0) {
            ret.push_back( (n - 1) % 26 + 'A');
            n = (n - 1)/ 26;
        }

        reverse(ret.begin(), ret.end());

        return ret;
    }
};