| 274 | } |
| 275 | |
| 276 | public static void main(String[] args) throws IOException { |
| 277 | BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); |
| 278 | StreamTokenizer in = new StreamTokenizer(br); |
| 279 | PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out)); |
| 280 | in.nextToken(); |
| 281 | n = (int) in.nval; |
| 282 | in.nextToken(); |
| 283 | m = (int) in.nval; |
| 284 | for (int i = 1, u, v; i < n; i++) { |
| 285 | in.nextToken(); |
| 286 | u = (int) in.nval; |
| 287 | in.nextToken(); |
| 288 | v = (int) in.nval; |
| 289 | addEdge(u, v); |
| 290 | addEdge(v, u); |
| 291 | } |
| 292 | for (int i = 1; i <= n; i++) { |
| 293 | in.nextToken(); |
| 294 | arr[i] = (int) in.nval; |
| 295 | } |
| 296 | dfs3(); // dfs3() 等同于 dfs1(1, 0)，调用迭代版防止爆栈 |
| 297 | dfs4(); // dfs4() 等同于 dfs2(1, 1)，调用迭代版防止爆栈 |
| 298 | build(1, n, 1); |
| 299 | in.nextToken(); |
| 300 | int root = (int) in.nval; |
| 301 | for (int i = 1, op, x, y, v; i <= m; i++) { |
| 302 | in.nextToken(); |
| 303 | op = (int) in.nval; |
| 304 | if (op == 1) { |
| 305 | in.nextToken(); |
| 306 | root = (int) in.nval; |
| 307 | } else if (op == 2) { |
| 308 | in.nextToken(); |
| 309 | x = (int) in.nval; |
| 310 | in.nextToken(); |
| 311 | y = (int) in.nval; |
| 312 | in.nextToken(); |
| 313 | v = (int) in.nval; |
| 314 | pathUpdate(x, y, v); |
| 315 | } else { |
| 316 | in.nextToken(); |
| 317 | x = (int) in.nval; |
| 318 | out.println(treeQuery(root, x)); |
| 319 | } |
| 320 | } |
| 321 | out.flush(); |
| 322 | out.close(); |
| 323 | br.close(); |
| 324 | } |
| 325 | |
| 326 | } |