Feat: 133. Clone Graph

Author: HC-kang

clone-graph/HC-kang.ts

@@ -0,0 +1,63 @@
+/**
+ * https://leetcode.com/problems/clone-graph
+ * T.C. O(N)
+ * S.C. O(N)
+ */
+function cloneGraph(node: _Node | null): _Node | null {
+  if (!node) return null;
+
+  const map = new Map<number, _Node>();
+  return dfs(node);
+
+  function dfs(node: _Node): _Node {
+    if (map.has(node.val)) return map.get(node.val)!;
+
+    const newNode = new _Node(node.val);
+    map.set(node.val, newNode);
+
+    for (let neighbor of node.neighbors) {
+      newNode.neighbors.push(dfs(neighbor));
+    }
+
+    return newNode;
+  }
+}
+
+/**
+ * T.C. O(N)
+ * S.C. O(N)
+ */
+function cloneGraph(node: _Node | null): _Node | null {
+  if (!node) return null;
+
+  const map = new Map<number, _Node>();
+  const stack = [node];
+  const newNode = new _Node(node.val);
+  map.set(node.val, newNode);
+
+  while (stack.length) {
+    const node = stack.pop()!;
+    const newNode = map.get(node.val)!;
+
+    for (let neighbor of node.neighbors) {
+      if (!map.has(neighbor.val)) {
+        stack.push(neighbor);
+        const newNeighbor = new _Node(neighbor.val);
+        map.set(neighbor.val, newNeighbor);
+      }
+      newNode.neighbors.push(map.get(neighbor.val)!);
+    }
+  }
+
+  return newNode;
+}
+
+class _Node {
+  val: number;
+  neighbors: _Node[];
+
+  constructor(val?: number, neighbors?: _Node[]) {
+    this.val = val === undefined ? 0 : val;
+    this.neighbors = neighbors === undefined ? [] : neighbors;
+  }
+}