Solve problem '168) excel sheet column title'

Author: ozantopal

problems/168-excel-sheet-column-title/README.md

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+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 <= 2^31 - 1`

problems/168-excel-sheet-column-title/main.go

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+package main
+
+import (
+	"fmt"
+)
+
+func main() {
+	fmt.Println(convertToTitle(1))
+	fmt.Println(convertToTitle(28))
+	fmt.Println(convertToTitle(701))
+}
+
+func convertToTitle(columnNumber int) string {
+	result := []byte{}
+	for columnNumber > 0 {
+		result = append(result, 'A'+byte((columnNumber-1)%26))
+		columnNumber = (columnNumber - 1) / 26
+	}
+	for i, j := 0, len(result)-1; i < j; i, j = i+1, j-1 {
+		result[i], result[j] = result[j], result[i]
+	}
+
+	return string(result)
+}