Create: 3286-find-a-safe-walk-through-a-grid.py

python/3286-find-a-safe-walk-through-a-grid.py

@@ -0,0 +1,35 @@
+from typing import List
+from collections import deque
+
+class Solution:
+    def findSafeWalk(self, grid: List[List[int]], health: int) -> bool:
+
+        m, n = len(grid), len(grid[0])
+
+        directions = [[0, 1], [0, -1], [1, 0], [-1, 0]]
+
+        queue = deque([(0, 0, health + (0 if grid[0][0] == 0 else -1))])
+
+        visited = [[-1] * n for _ in range(m)]
+        visited[0][0] = health + (0 if grid[0][0] == 0 else -1)
+
+        while queue:
+            x, y, cur_health = queue.popleft()
+
+            for dx, dy in directions:
+                nx, ny = x + dx, y + dy
+
+                if 0 > nx or 0 > ny or nx >= m or ny >= n :
+                    continue
+
+                new_health = cur_health - grid[nx][ny]
+
+                if nx == m-1 and ny == n-1 and new_health > 0:
+                    return True
+
+
+                if new_health > visited[nx][ny]:
+                    visited[nx][ny] = new_health
+                    queue.append((nx, ny, new_health))
+
+        return False