Given a string s of lower and upper case English letters.
A good string is a string which doesn't have two adjacent characters s[i] and s[i + 1] where:
0 <= i <= s.length - 2s[i] is a lower-case letter and s[i + 1] is the same letter but in upper-case or vice-versa.To make the string good, you can choose two adjacent characters that make the string bad and remove them. You can keep doing this until the string becomes good.
+ +Return the string after making it good. The answer is guaranteed to be unique under the given constraints.
+ +Notice that an empty string is also good.
+ ++
Example 1:
+ ++Input: s = "leEeetcode" +Output: "leetcode" +Explanation: In the first step, either you choose i = 1 or i = 2, both will result "leEeetcode" to be reduced to "leetcode". ++ +
Example 2:
+ ++Input: s = "abBAcC" +Output: "" +Explanation: We have many possible scenarios, and all lead to the same answer. For example: +"abBAcC" --> "aAcC" --> "cC" --> "" +"abBAcC" --> "abBA" --> "aA" --> "" ++ +
Example 3:
+ ++Input: s = "s" +Output: "s" ++ +
+
Constraints:
+ +1 <= s.length <= 100s contains only lower and upper case English letters.