[ PS ] : Graph Valid Tree

Author: uraflower

graph-valid-tree/uraflower.js

@@ -0,0 +1,39 @@
+/**
+ * @param {number} n
+ * @param {number[][]} edges
+ * @returns {boolean}
+ */
+function validTree(n, edges) {
+    //  트리의 조건을 만족하는지 확인(V = E + 1)
+    if (edges.length !== n - 1) {
+        return false;
+    }
+
+    const graph = Array.from({ length: n }).map(() => []);
+
+    for (const [u, v] of edges) {
+        graph[u].push(v);
+        graph[v].push(u);
+    }
+
+    const queue = [[-1, 0]]; // 부모 노드, 자식 노드
+    const visited = new Set();
+
+    while (queue.length) {
+        const [parent, current] = queue.shift();
+        if (visited.has(current)) {
+            return false;
+        }
+        visited.add(current);
+
+        for (const neighbor of graph[current]) {
+            if (neighbor === parent) continue;
+            queue.push([current, neighbor]);
+        }
+    }
+
+    return visited.size === n;
+}
+
+// 시간복잡도: O(V + E)
+// 공간복잡도: O(V)