Create solution.py

Author: Muawiya-contact

Medium/3170. Lexicographically Minimum String After Removing Stars/solution.py

@@ -0,0 +1,22 @@
+import heapq
+from collections import defaultdict, deque
+
+class Solution(object):
+    def clearStars(self, s):
+        n = len(s)
+        pq = []  # Min-heap to store characters
+        m = defaultdict(deque)  # Map character -> deque of indices
+        keep = [True] * n  # Marks whether to keep character at index
+
+        for i in range(n):
+            if s[i] == '*':
+                smallest = heapq.heappop(pq)  # Get smallest character
+                idx = m[smallest].pop()      # Remove last occurrence index
+                keep[i] = False              # Mark '*' for removal
+                keep[idx] = False            # Mark smallest char for removal
+            else:
+                heapq.heappush(pq, s[i])
+                m[s[i]].append(i)
+
+        # Build result from characters not marked for removal
+        return ''.join(s[i] for i in range(n) if keep[i])