diff --git "a/LiiNi-coder/202601/24 BOJ \353\266\201\354\252\275\353\202\230\353\235\274\354\235\230 \353\217\204\353\241\234.md" "b/LiiNi-coder/202601/24 BOJ \353\266\201\354\252\275\353\202\230\353\235\274\354\235\230 \353\217\204\353\241\234.md"
new file mode 100644
index 00000000..b3bca148
--- /dev/null
+++ "b/LiiNi-coder/202601/24 BOJ \353\266\201\354\252\275\353\202\230\353\235\274\354\235\230 \353\217\204\353\241\234.md"	
@@ -0,0 +1,69 @@
+```java
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.util.ArrayDeque;
+import java.util.ArrayList;
+import java.util.Deque;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+public class Main{
+	private static Map<Integer, List<int[]>> graph = new HashMap<>();
+	private static int N = 0;
+	public static void main(String[] args) throws IOException {
+		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
+		while(true){
+			String line= br.readLine();
+			if(line == null  || line.trim().isEmpty()){
+				break;
+			}
+			String[] tokens = line.split(" ");
+			int a = Integer.parseInt(tokens[0]);
+			int b = Integer.parseInt(tokens[1]);
+			int w = Integer.parseInt(tokens[2]);
+			graph.putIfAbsent(a, new ArrayList<>());
+			graph.putIfAbsent(b, new ArrayList<>());
+			graph.get(a).add(new int[]{b, w});
+			graph.get(b).add(new int[]{a, w});
+			N = Math.max(N, a);
+			N = Math.max(N, b);
+		}
+		//트리의 지름 : 아무점에서 최장거리 가지는 노드 구하고
+		// 해당 노드에서 또 최장거리를 구한것이 트리의 지름
+		int[] r1 = bfs(1);
+		int[] r2 = bfs(r1[0]);
+		System.out.println(r2[1]);
+	}
+
+	static int[] bfs(int start) {
+		boolean[] visited = new boolean[N + 1];
+		Deque<int[]> q = new ArrayDeque<>();
+		q.offer(new int[]{start, 0});
+		visited[start] = true;
+
+		int far = start;
+		int max = 0;
+
+		while (!q.isEmpty()) {
+			int[] cur = q.poll();
+			int v = cur[0];
+			int d = cur[1];
+			if (d > max) {
+				max = d;
+				far = v;
+			}
+			for (int[] next : graph.get(v)) {
+				int nv = next[0];
+				int w = next[1];
+				if (!visited[nv]) {
+					visited[nv] = true;
+					q.offer(new int[]{nv, d + w});
+				}
+			}
+		}
+		return new int[]{far, max};
+	}
+}
+```