DFS yummy

Author: ggjae

cpp/11725.cpp

@@ -0,0 +1,40 @@
+#include <iostream>
+#include <vector>
+
+using namespace std;
+const int MAX = 100000 + 1;
+int N;
+bool visited[MAX];
+int parent[MAX];
+vector<int> tree[MAX];
+void findParent(int nodeNum)
+{
+    visited[nodeNum] = true; //방문한 노드 표시
+    //DFS
+    for (int i = 0; i<tree[nodeNum].size(); i++)
+    {
+        int next = tree[nodeNum][i];
+        if (!visited[next])
+        {
+            parent[next] = nodeNum; //next의 parent는 nodeNum
+            findParent(next);
+        }
+    }
+}
+int main(void)
+{
+    ios_base::sync_with_stdio(0);
+    cin.tie(0);
+    cin >> N;
+    for (int i = 0; i < N - 1; i++)
+    {
+        int node1, node2;
+        cin >> node1 >> node2;
+        tree[node1].push_back(node2);
+        tree[node2].push_back(node1);
+    }
+        findParent(1); //root부터
+    for (int i = 2; i <= N; i++)
+        cout << parent[i] << "\n";
+    return 0;
+}