Time: 131 ms (60.96%) | Memory: 19.2 MB (99.88%) - LeetSync

Author: joshua-dierickse-alt

542-01-matrix/01-matrix.py

@@ -0,0 +1,37 @@
+from collections import deque
+
+direction = [(1, 0), (0, 1), (-1, 0), (0, -1)]
+
+class Solution:
+    def updateMatrix(self, mat: List[List[int]]) -> List[List[int]]:
+        q = deque([])
+
+        for i in range(len(mat)):
+            for j in range(len(mat[i])):
+                if mat[i][j] == 1:
+                    mat[i][j] = None
+                else:
+                    q.append((i, j))
+
+        d = 1
+
+        while q:
+            n = len(q)
+
+            for i in range(len(q)):
+                x, y = q.popleft()
+
+                for dx, dy in direction:
+                    nx = dx + x
+                    ny = dy + y
+                    if 0 <= nx < len(mat) and 0 <= ny < len(mat[0]) and mat[nx][ny] == None:
+                        mat[nx][ny] = d
+                        q.append((nx, ny))
+
+            d += 1
+
+        return mat
+
+
+                    
+