From 7806b4db8d4cb347edf2c6f344c5687e5024de0c Mon Sep 17 00:00:00 2001 From: Ukj0ng <90972240+Ukj0ng@users.noreply.github.com> Date: Sat, 6 Dec 2025 21:13:31 +0900 Subject: [PATCH] =?UTF-8?q?[20251206]=20BOJ=20/=20G2=20/=20=ED=99=98?= =?UTF-8?q?=EC=8A=B9=20/=20=ED=95=9C=EC=A2=85=EC=9A=B1?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../06 BOJ G2 \355\231\230\354\212\271.md" | 87 +++++++++++++++++++ 1 file changed, 87 insertions(+) create mode 100644 "Ukj0ng/202512/06 BOJ G2 \355\231\230\354\212\271.md" diff --git "a/Ukj0ng/202512/06 BOJ G2 \355\231\230\354\212\271.md" "b/Ukj0ng/202512/06 BOJ G2 \355\231\230\354\212\271.md" new file mode 100644 index 00000000..bd9ba1bb --- /dev/null +++ "b/Ukj0ng/202512/06 BOJ G2 \355\231\230\354\212\271.md" @@ -0,0 +1,87 @@ +``` +import java.io.*; +import java.util.*; + +public class Main { + private static final BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); + private static final BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(System.out)); + private static List[] edges; + private static BitSet[] tubes; + private static Set start, end; + private static boolean[] visited; + private static int N, K, M; + + public static void main(String[] args) throws IOException { + init(); + int answer = N!=1 ? BFS() : 1; + + bw.write(answer + "\n"); + bw.flush(); + bw.close(); + br.close(); + } + + private static void init() throws IOException { + StringTokenizer st = new StringTokenizer(br.readLine()); + N = Integer.parseInt(st.nextToken()); + K = Integer.parseInt(st.nextToken()); + M = Integer.parseInt(st.nextToken()); + + edges = new List[M]; + tubes = new BitSet[M]; + visited = new boolean[M]; + start = new HashSet<>(); + end = new HashSet<>(); + + for (int i = 0; i < M; i++) { + edges[i] = new ArrayList<>(); + tubes[i] = new BitSet(); + } + + for (int i = 0; i < M; i++) { + st = new StringTokenizer(br.readLine()); + for (int j = 0; j < K; j++) { + int num = Integer.parseInt(st.nextToken()); + tubes[i].set(num); + if (num == 1) start.add(i); + if (num == N) end.add(i); + } + } + + for (int i = 0; i < M-1; i++) { + for (int j = i+1; j < M; j++) { + if (tubes[i].intersects(tubes[j])) { + edges[i].add(j); + edges[j].add(i); + } + } + } + } + + private static int BFS() { + Queue q = new ArrayDeque<>(); + int result = -1; + for (int s : start) { + visited[s] = true; + q.add(new int[]{s, 2}); + } + + while (!q.isEmpty()) { + int[] current = q.poll(); + + if (end.contains(current[0])) { + result = current[1]; + break; + } + + for (int next : edges[current[0]]) { + if (visited[next]) continue; + visited[next] = true; + q.add(new int[]{next, current[1]+1}); + } + } + + return result; + } +} +```