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"
Example 4:
Input: columnNumber = 2147483647 Output: "FXSHRXW"
Constraints:
1 <= columnNumber <= 231 - 1
Solution: Base conversion
Time complexity: O(logn)
Space complexity: O(logn)
C++
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// Author: Huahua class Solution { public: string convertToTitle(int n) { string ans; do { n--; ans += 'A' + (char)(n % 26); n /= 26; } while (n); reverse(begin(ans), end(ans)); return ans; } }; |