feat(leetcode): solve 130 - Surrounded Regions

Author: arnav-on-code

README.md

@@ -9,33 +9,33 @@ Automatically synchronize accepted LeetCode submissions to GitHub.
 ```text
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-Solved: 127 / 300 Problems
+Solved: 128 / 300 Problems
 
 📊 Statistics
 Difficulty	Solved
 🟢 Easy	63
-🟡 Medium	58
+🟡 Medium	59
 🔴 Hard	6
-Total	127
+Total	128
 🔥 Latest Accepted Problem
 
 
 | Field | Value |
 |------|------|
-| Problem ID | 4136 |
-| Title | Concatenate Non Zero Digits And Multiply By Sum Ii |
+| Problem ID | 130 |
+| Title | Surrounded Regions |
 | Language | Python3 |
-| Runtime | 361 ms |
-| Memory | 57.8 MB |
+| Runtime | 8 ms |
+| Memory | 22.3 MB |
 
 
 💻 Languages Used
 
-- **Python3** : 86
+- **Python3** : 87
 
 ## 📚 Recent Accepted Problems
 
-- 4136 Concatenate Non Zero Digits And Multiply By Sum Ii
+- 130 Surrounded Regions
 - 4136 Concatenate Non Zero Digits And Multiply By Sum Ii
 - 4136 Concatenate Non Zero Digits And Multiply By Sum Ii
 - 4136 Concatenate Non Zero Digits And Multiply By Sum Ii
@@ -81,4 +81,4 @@ Git
 GitHub
 ⏰ Last Sync
 
-2026-07-10 14:25:27
+2026-07-10 19:26:33

storage/solutions/0130_Surrounded_Regions/metadata.json

@@ -0,0 +1,11 @@
+{
+    "submission_id": "2062990749",
+    "question_id": "130",
+    "title_slug": "surrounded-regions",
+    "language": "python3",
+    "language_verbose": "Python3",
+    "runtime": "8 ms",
+    "memory": "22.3 MB",
+    "status_code": 10,
+    "timestamp": 1783696237
+}

storage/solutions/0130_Surrounded_Regions/solution.py

@@ -0,0 +1,48 @@
+class Solution:
+    def solve(self, board: List[List[str]]) -> None:
+        """
+        Do not return anything, modify board in-place instead.
+        """
+
+        rows = len(board)
+        cols = len(board[0])
+
+        def dfs(r, c):
+
+            if (
+                r < 0 or
+                c < 0 or
+                r >= rows or
+                c >= cols or
+                board[r][c] != "O"
+            ):
+                return
+
+            board[r][c] = "T"
+
+            dfs(r+1, c)
+            dfs(r-1, c)
+            dfs(r, c+1)
+            dfs(r, c-1)
+
+        # Left & Right borders
+        for r in range(rows):
+
+            dfs(r, 0)
+            dfs(r, cols-1)
+
+        # Top & Bottom borders
+        for c in range(cols):
+
+            dfs(0, c)
+            dfs(rows-1, c)
+
+        # Flip / Restore
+        for r in range(rows):
+            for c in range(cols):
+
+                if board[r][c] == "O":
+                    board[r][c] = "X"
+
+                elif board[r][c] == "T":
+                    board[r][c] = "O"

storage/stats.json

@@ -1,15 +1,15 @@
 {
-    "total": 127,
+    "total": 128,
     "easy": 63,
-    "medium": 58,
+    "medium": 59,
     "hard": 6,
     "languages": {
-        "Python3": 86
+        "Python3": 87
     },
     "recent_problems": [
         {
-            "id": "4136",
-            "title": "Concatenate Non Zero Digits And Multiply By Sum Ii"
+            "id": "130",
+            "title": "Surrounded Regions"
         },
         {
             "id": "4136",
@@ -29,11 +29,11 @@
         }
     ],
     "last_problem": {
-        "id": "4136",
-        "title": "Concatenate Non Zero Digits And Multiply By Sum Ii",
+        "id": "130",
+        "title": "Surrounded Regions",
         "language": "Python3",
-        "runtime": "361 ms",
-        "memory": "57.8 MB"
+        "runtime": "8 ms",
+        "memory": "22.3 MB"
     },
-    "last_sync": "2026-07-10 14:25:27"
+    "last_sync": "2026-07-10 19:26:33"
 }