Create 733-flood_fill.py

Author: stevestar888

Diff for: 733-flood_fill.py

@@ -0,0 +1,90 @@
+"""
+https://leetcode.com/problems/flood-fill/submissions/
+
+Stats: O(n) time, O(n) space
+    Runtime: 72 ms, faster than 23.24% of Python online submissions for Flood Fill.
+    Memory Usage: 13 MB, less than 24.83% of Python online submissions for Flood Fill.
+"""
+class Solution(object):
+    """
+    First take (uses unecessary set)
+    """
+    def floodFill(self, image, source_row, source_col, new_color):
+        """
+        :type image: List[List[int]]
+        :type sr: int
+        :type sc: int
+        :type newColor: int
+        :rtype: List[List[int]]
+        """
+        visited = set()
+        self.old_color = image[source_row][source_col]
+        self.image = image
+        
+        def fill(sr, sc):
+            if (str(sr) + str(sc)) in visited:
+                return
+            
+            visited.add(str(sr) + str(sc))
+            
+            length = len(self.image)
+            height = len(self.image[0]) 
+            
+            # print(visited)
+            # print(sr, sc)
+            # print(self.image)
+            
+            if 0 <= sr < length and 0 <= sc < height: #check bounds
+                if self.image[sr][sc] == self.old_color:
+                    self.image[sr][sc] = new_color
+                    # print("updated {} {} ".format(sr, sc))
+                    # print(self.image)
+                    # print("")
+
+                    #check four sides
+                    fill(sr + 1, sc)
+                    fill(sr - 1, sc)
+                    fill(sr, sc + 1)
+                    fill(sr, sc - 1)
+        
+        # do our fill work
+        fill(source_row, source_col)
+        
+        return self.image
+    
+    """
+    Improved -- no set & uses clever bounds checking
+    """
+    def floodFill(self, image, source_row, source_col, new_color):
+        """
+        :type image: List[List[int]]
+        :type sr: int
+        :type sc: int
+        :type newColor: int
+        :rtype: List[List[int]]
+        """
+        if image[source_row][source_col] == new_color:
+            return image
+        
+        old_color = image[source_row][source_col]
+        
+        def fill(sr, sc):
+            if sr < 0 or sc < 0:
+                return
+            
+            # use exception handling instead of bounds checking
+            try:
+                if image[sr][sc] == old_color:
+                    image[sr][sc] = new_color
+
+                    #check four sides
+                    fill(sr + 1, sc)
+                    fill(sr - 1, sc)
+                    fill(sr, sc + 1)
+                    fill(sr, sc - 1)
+            except: #MUST have this otherwise error!
+                return
+        
+        # do the dfs dirty work
+        fill(source_row, source_col)
+        return image