Merge pull request #579 from aishwarya-chandra/day11q1

day11q1

Day-11/Find Eventual Safe States/aishwarya--py.md

@@ -0,0 +1,34 @@
+```
+class Solution:
+    def eventualSafeNodes(self, graph: List[List[int]]) -> List[int]:
+        n = len(graph)
+        visited = [False] * n
+        unsafe = [0] * n
+
+        for i in range(n):
+            if unsafe[i] == 0:
+                visited[i] = True
+                self.dfs(i, visited, graph, unsafe)
+                visited[i] = False
+
+        result = []
+        for i in range(len(unsafe)):
+            if unsafe[i] == 1:
+                result.append(i)
+        return result
+
+    def dfs(self, node: int, visited: List[bool], graph: List[List[int]], unsafe: List[int]) -> bool:
+        isSafe = True
+        for neighbor in graph[node]:
+            if visited[neighbor] or unsafe[neighbor] == 2:
+                isSafe = False
+                break
+            if unsafe[neighbor] == 1:
+                continue
+            visited[neighbor] = True
+            if not self.dfs(neighbor, visited, graph, unsafe):
+                isSafe = False
+            visited[neighbor] = False
+        unsafe[node] = 1 if isSafe else 2
+        return isSafe
+```