Create 2192. All Ancestors of a Node in a Directed Acyclic Graph (#516)

Author: Chayandas07

2192. All Ancestors of a Node in a Directed Acyclic Graph

@@ -0,0 +1,23 @@
+class Solution {
+public:
+    vector<vector<int>> getAncestors(int n, vector<vector<int>>& edges) {
+        vector<vector<int>> ans(n), directChild(n);
+        for (auto& e : edges) {
+            directChild[e[0]].push_back(e[1]);
+        }
+        for (int i = 0; i < n; i++) {
+            dfs(i, i, ans, directChild);
+        }
+        return ans;
+    }
+
+private:
+    void dfs(int x, int curr, vector<vector<int>>& ans, vector<vector<int>>& directChild) {
+        for (int ch : directChild[curr]) {
+            if (ans[ch].empty() || ans[ch].back() != x) {
+                ans[ch].push_back(x);
+                dfs(x, ch, ans, directChild);
+            }
+        }
+    }
+};