Create RemovStars.java

Leetcode/RemovStars.java

@@ -0,0 +1,58 @@
+/**
+2390. Removing Stars From a String
+Solved
+Medium
+Topics
+Companies
+Hint
+You are given a string s, which contains stars *.
+
+In one operation, you can:
+
+Choose a star in s.
+Remove the closest non-star character to its left, as well as remove the star itself.
+Return the string after all stars have been removed.
+
+Note:
+
+The input will be generated such that the operation is always possible.
+It can be shown that the resulting string will always be unique.
+ 
+**/
+
+class Solution {
+    public String removeStars(String s) {
+        Stack<Character> st = new Stack<>();
+        for(int i=0;i<s.length();i++){
+
+            if(s.charAt(i)=='*'){
+               st.pop();
+            }
+            else{
+                st.push(s.charAt(i));
+            }
+        }
+        StringBuilder sb = new StringBuilder();
+        while(!st.isEmpty()){
+            sb.append(st.pop());
+        }
+        sb.reverse();
+         return sb.toString();
+
+
+    }
+
+  public String removestarsBest(String s){
+     int len = s.length();
+        byte[] res = new byte[len];
+        s.getBytes(0,len,res,0);
+        int countStars = 0;
+        for(int i = 0; i<len; i++)
+        {
+            if(res[i] == '*') countStars++;
+            else res[i-countStars*2] = res[i];
+        }
+        return new String(res, 0, len-countStars*2);
+  }
+
+}