Merge pull request neetcode-gh#3346 from adhamahmad/Create-1898-Maximum-Number-of-Removable-Characters.java

sujal-goswami · web-flow · commit 545caed2cd36 · 2024-03-14T18:18:01.000+05:30
Create: 1898-maximum-number-of-removable-characters.java
diff --git a/java/1898-maximum-number-of-removable-characters.java b/java/1898-maximum-number-of-removable-characters.java
@@ -0,0 +1,36 @@
+class Solution {
+
+    public int maximumRemovals(String s, String p, int[] removable) {
+        int left =0;
+        int right = removable.length -1;
+        int result =0;
+        while(left <= right){
+            HashSet<Integer> removed = new HashSet<>();
+            int mid = (left+right)/2;
+            for(int i =0; i <= mid; i++){ // populate the hashset
+                removed.add(removable[i]);
+            }
+            if(isSubseq(s,p,removed)){
+                result = Math.max(result,mid+1);
+                left = mid+1; // greedy try to find even a higher value
+            }else{
+                right = mid -1;
+            }
+        }
+        return result;
+    }
+
+    private boolean isSubseq(String s , String subseq,HashSet<Integer> removed){
+        int i1 =0;
+        int i2 =0;
+        while(i1 < s.length() && i2 < subseq.length()){
+            if( s.charAt(i1) != subseq.charAt(i2) || removed.contains(i1) ){
+                i1++;
+            }else{
+                i1++;
+                i2++;
+            }
+        }
+        return i2 == subseq.length();
+    }
+}
