Reverse vowels done + some comments refactoring

Author: rampatra

src/main/java/com/leetcode/strings/AnagramsInString.java

@@ -13,7 +13,7 @@
 public class AnagramsInString {
 
     /**
-     * Time complexity: O ((n-m) * m log m)
+     * Time complexity: O((n-m) * m log m)
      * where,
      * n = text length
      * m = pattern length
@@ -50,10 +50,11 @@ private static List<Integer> findAllAnagramsInTextNaive(String text, String patt
     }
 
     /**
-     * Completes within <a href="https://leetcode.com/submissions/detail/222911434/">7ms on leetcode.</a>
      * Time complexity: O(n)
      * where,
      * n = length of text or number of characters in text
+     * <p>
+     * Runtime: <a href="https://leetcode.com/submissions/detail/222911434/">7 ms on leetcode</a>.
      *
      * @param text
      * @param pattern

src/main/java/com/leetcode/strings/ReverseVowels.java

@@ -0,0 +1,65 @@
+package com.leetcode.strings;
+
+/**
+ * Leetcode Problem: https://leetcode.com/problems/reverse-vowels-of-a-string/
+ *
+ * @author rampatra
+ * @since 2019-04-19
+ */
+public class ReverseVowels {
+
+    /**
+     * Reverse only the vowels in the string {@code str}.
+     * <p>
+     * Time Complexity: O(n)
+     * where,
+     * n = no. of characters in the string
+     * <p>
+     * Runtime: <a href="https://leetcode.com/submissions/detail/223519160/">2 ms on leetcode</a>.
+     *
+     * @param str
+     * @return
+     */
+    private static String reverseVowels(String str) {
+
+        char[] chars = str.toCharArray();
+        char temp;
+        int left = 0;
+        int right = str.length() - 1;
+
+        while (left < right) {
+            // find the vowel from left
+            while (!isVowel(chars[left]) && left < right) {
+                left++;
+            }
+            // find the vowel from right
+            while (!isVowel(chars[right]) && left < right) {
+                right--;
+            }
+
+            if (!isVowel(chars[left]) || !isVowel(chars[right])) {
+                break;
+            }
+
+            // swap the characters
+            temp = chars[left];
+            chars[left] = chars[right];
+            chars[right] = temp;
+
+            left++;
+            right--;
+        }
+        return new String(chars);
+    }
+
+    private static boolean isVowel(char c) {
+        return c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' ||
+                c == 'A' || c == 'E' || c == 'I' || c == 'O' || c == 'U';
+    }
+
+    public static void main(String[] args) {
+        System.out.println(reverseVowels("hello"));
+        System.out.println(reverseVowels("a"));
+        System.out.println(reverseVowels(""));
+    }
+}

src/main/java/com/leetcode/strings/StringCompression.java

@@ -0,0 +1,15 @@
+package com.leetcode.strings;
+
+/**
+ * @author rampatra
+ * @since 2019-04-16
+ */
+public class StringCompression {
+    
+    private static int compress(char[] chars) {
+        return -1;
+    }
+    
+    public static void main(String[] args) {
+    }
+}

src/main/java/com/leetcode/strings/UniqueCharacterInString.java

@@ -9,8 +9,8 @@
 public class UniqueCharacterInString {
 
     /**
-     * Completes within <a href="https://leetcode.com/submissions/detail/222914261/">7ms on leetcode.</a>
      * Time complexity: O(n)
+     * Runtime: <a href="https://leetcode.com/submissions/detail/222914261/">7 ms on leetcode</a>.
      *
      * @param str the input string
      * @return the index of the first non-repeating character in {@code str}, {@code -1} otherwise.