結果
問題 | No.763 Noelちゃんと木遊び |
ユーザー |
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提出日時 | 2018-12-13 01:45:12 |
言語 | Java (openjdk 23) |
結果 |
AC
|
実行時間 | 312 ms / 2,000 ms |
コード長 | 3,376 bytes |
コンパイル時間 | 2,934 ms |
コンパイル使用メモリ | 89,872 KB |
実行使用メモリ | 75,140 KB |
最終ジャッジ日時 | 2024-09-25 04:03:38 |
合計ジャッジ時間 | 9,907 ms |
ジャッジサーバーID (参考情報) |
judge4 / judge5 |
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ファイルパターン | 結果 |
---|---|
other | AC * 21 |
ソースコード
public class Main {private static void solve() {int n = ni();int[] from = new int[n - 1];int[] to = new int[n - 1];for (int i = 0; i < n - 1; i++) {from[i] = ni() - 1;to[i] = ni() - 1;}int[][] g = packU(n, from, to);int[] ret = dfs(0, -1, g);System.out.println(Math.max(ret[0], ret[1]));}private static int[] dfs(int now, int pre, int[][] g) {int[] ret = {0, 1};for (int next : g[now]) {if (next == pre)continue;int[] v = dfs(next, now, g);ret[0] += Math.max(v[0], v[1]);ret[1] += Math.max(v[0], v[1] - 1);}return ret;}static int[][] packU(int n, int[] from, int[] to) {int[][] g = new int[n][];int[] p = new int[n];for (int f : from)p[f]++;for (int t : to)p[t]++;for (int i = 0; i < n; i++)g[i] = new int[p[i]];for (int i = 0; i < from.length; i++) {g[from[i]][--p[from[i]]] = to[i];g[to[i]][--p[to[i]]] = from[i];}return g;}public static void main(String[] args) {new Thread(null, new Runnable() {@Overridepublic void run() {long start = System.currentTimeMillis();String debug = args.length > 0 ? args[0] : null;if (debug != null) {try {is = java.nio.file.Files.newInputStream(java.nio.file.Paths.get(debug));} catch (Exception e) {throw new RuntimeException(e);}}reader = new java.io.BufferedReader(new java.io.InputStreamReader(is), 32768);solve();out.flush();tr((System.currentTimeMillis() - start) + "ms");}}, "", 64000000).start();}private static java.io.InputStream is = System.in;private static java.io.PrintWriter out = new java.io.PrintWriter(System.out);private static java.util.StringTokenizer tokenizer = null;private static java.io.BufferedReader reader;public static String next() {while (tokenizer == null || !tokenizer.hasMoreTokens()) {try {tokenizer = new java.util.StringTokenizer(reader.readLine());} catch (Exception e) {throw new RuntimeException(e);}}return tokenizer.nextToken();}private static double nd() {return Double.parseDouble(next());}private static long nl() {return Long.parseLong(next());}private static int[] na(int n) {int[] a = new int[n];for (int i = 0; i < n; i++)a[i] = ni();return a;}private static char[] ns() {return next().toCharArray();}private static long[] nal(int n) {long[] a = new long[n];for (int i = 0; i < n; i++)a[i] = nl();return a;}private static int[][] ntable(int n, int m) {int[][] table = new int[n][m];for (int i = 0; i < n; i++) {for (int j = 0; j < m; j++) {table[i][j] = ni();}}return table;}private static int[][] nlist(int n, int m) {int[][] table = new int[m][n];for (int i = 0; i < n; i++) {for (int j = 0; j < m; j++) {table[j][i] = ni();}}return table;}private static int ni() {return Integer.parseInt(next());}private static void tr(Object... o) {if (is != System.in)System.out.println(java.util.Arrays.deepToString(o));}}