文章目录
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
cpp
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;
}
};