solve #168

Author: aylei

Diff for: src/lib.rs

@@ -155,3 +155,4 @@ mod n0164_maximum_gap;
 mod n0165_compare_version_numbers;
 mod n0166_fraction_to_recurring_decimal;
 mod n0167_two_sum_ii_input_array_is_sorted;
+mod n0168_excel_sheet_column_title;

Diff for: src/n0168_excel_sheet_column_title.rs

@@ -0,0 +1,72 @@
+/**
+ * [168] Excel Sheet Column Title
+ *
+ * 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"
+ * 
+ */
+pub struct Solution {}
+
+// submission codes start here
+
+impl Solution {
+    pub fn convert_to_title(n: i32) -> String {
+        let base = 26;
+        let mut n = n;
+        let mut res = Vec::new();
+        while n > 0 {
+            let mut code = (n % base) as u8;
+            n = n / base;
+            if code == 0 { n -= 1; code = base as u8; };
+            let alphabetic = (('A' as u8) + (code - 1_u8)) as char;
+            res.push(alphabetic);
+        }
+        res.reverse();
+        res.into_iter().collect()
+    }
+}
+
+// submission codes end
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_168() {
+        assert_eq!(Solution::convert_to_title(28), "AB".to_owned());
+        assert_eq!(Solution::convert_to_title(1), "A".to_owned());
+    }
+}