結果
| 問題 | No.364 門松木 |
| ユーザー |
 uwi
|
| 提出日時 | 2016-03-24 04:22:55 |
| 言語 | Java (openjdk 23) |
| 結果 |
AC
|
| 実行時間 | 714 ms / 3,000 ms |
| コード長 | 6,815 bytes |
| コンパイル時間 | 3,759 ms |
| コンパイル使用メモリ | 87,220 KB |
| 実行使用メモリ | 50,028 KB |
| 最終ジャッジ日時 | 2024-10-01 21:50:10 |
| 合計ジャッジ時間 | 17,956 ms |
|
ジャッジサーバーID （参考情報） |
judge5 / judge2 |
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| ファイルパターン | 結果 |
|---|---|
| sample | AC * 3 |
| other | AC * 31 |
ソースコード
package contest;import java.io.ByteArrayInputStream;import java.io.IOException;import java.io.InputStream;import java.io.PrintWriter;import java.util.Arrays;import java.util.InputMismatchException;public class Q1009 {InputStream is;PrintWriter out;String INPUT = "";void solve(){int n = ni();if(!(n >= 1))throw new AssertionError();if(!(n <= 50000))throw new AssertionError();int[] a = na(n);for(int v : a){if(!(v >= 1))throw new AssertionError();if(!(v <= 1000))throw new AssertionError();}int[] from = new int[n - 1];int[] to = new int[n - 1];DJSet ds = new DJSet(n);for (int i = 0; i < n - 1; i++) {from[i] = ni() - 1;to[i] = ni() - 1;if(!(from[i] >= 0))throw new AssertionError();if(!(from[i] < n))throw new AssertionError();if(!(to[i] >= 0))throw new AssertionError();if(!(to[i] < n))throw new AssertionError();if(!(to[i] != from[i]))throw new AssertionError();ds.union(from[i], to[i]);}if(!(ds.count() == 1))throw new AssertionError();int[][] g = packU(n, from, to);int[][] pars = parents3(g, 0);int[] par = pars[0], ord = pars[1], dep = pars[2];int Z = 1001;// 1個上の親に遠慮した最高スコアlong[] big = new long[n];long[] small = new long[n];long ret = 0;for(int i = n-1;i >= 0;i--){int cur = ord[i];// curがbig{long[] valscores = new long[Z];Arrays.fill(valscores, -1);for(int e : g[cur]){if(par[cur] != e && a[e] < a[cur]){valscores[a[e]] = Math.max(valscores[a[e]], small[e]);}}long score = 0;long hand = 0;for(long v : valscores){if(v >= 0){hand++;score += v;}}// curがrootの場合のスコアret = Math.max(ret, score+hand*(hand-1)/2);if(par[cur] != -1 && a[cur] > a[par[cur]]){if(valscores[a[par[cur]]] != -1){// 親と同じ値をのぞいて親を選ぶscore -= valscores[a[par[cur]]];}else{// 親をただ選ぶhand++;}big[cur] = score + hand*(hand-1)/2;}}// curがsmall{long[] valscores = new long[Z];Arrays.fill(valscores, -1);for(int e : g[cur]){if(par[cur] != e && a[e] > a[cur]){valscores[a[e]] = Math.max(valscores[a[e]], big[e]);}}long score = 0;long hand = 0;for(long v : valscores){if(v >= 0){hand++;score += v;}}// curがrootの場合のスコアret = Math.max(ret, score+hand*(hand-1)/2);if(par[cur] != -1 && a[cur] < a[par[cur]]){if(valscores[a[par[cur]]] != -1){// 親と同じ値をのぞいて親を選ぶscore -= valscores[a[par[cur]]];}else{// 親をただ選ぶhand++;}small[cur] = score + hand*(hand-1)/2;}}}out.println(ret);}public static class DJSet {public int[] upper;public DJSet(int n) {upper = new int[n];Arrays.fill(upper, -1);}public int root(int x) {return upper[x] < 0 ? x : (upper[x] = root(upper[x]));}public boolean equiv(int x, int y) {return root(x) == root(y);}public boolean union(int x, int y) {x = root(x);y = root(y);if (x != y) {if (upper[y] < upper[x]) {int d = x;x = y;y = d;}upper[x] += upper[y];upper[y] = x;}return x == y;}public int count() {int ct = 0;for (int u : upper)if (u < 0)ct++;return ct;}}public static int[][] parents3(int[][] g, int root) {int n = g.length;int[] par = new int[n];Arrays.fill(par, -1);int[] depth = new int[n];depth[0] = 0;int[] q = new int[n];q[0] = root;for (int p = 0, r = 1; p < r; p++) {int cur = q[p];for (int nex : g[cur]) {if (par[cur] != nex) {q[r++] = nex;par[nex] = cur;depth[nex] = depth[cur] + 1;}}}return new int[][] { par, q, depth };}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;}void run() throws Exception{is = INPUT.isEmpty() ? System.in : new ByteArrayInputStream(INPUT.getBytes());out = new PrintWriter(System.out);long s = System.currentTimeMillis();solve();out.flush();if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");}public static void main(String[] args) throws Exception { new Q1009().run(); }private byte[] inbuf = new byte[1024];private int lenbuf = 0, ptrbuf = 0;private int readByte(){if(lenbuf == -1)throw new InputMismatchException();if(ptrbuf >= lenbuf){ptrbuf = 0;try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); }if(lenbuf <= 0)return -1;}return inbuf[ptrbuf++];}private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); }private int skip() { int b; while((b = readByte()) != -1 && isSpaceChar(b)); return b; }private double nd() { return Double.parseDouble(ns()); }private char nc() { return (char)skip(); }private String ns(){int b = skip();StringBuilder sb = new StringBuilder();while(!(isSpaceChar(b))){ // when nextLine, (isSpaceChar(b) && b != ' ')sb.appendCodePoint(b);b = readByte();}return sb.toString();}private char[] ns(int n){char[] buf = new char[n];int b = skip(), p = 0;while(p < n && !(isSpaceChar(b))){buf[p++] = (char)b;b = readByte();}return n == p ? buf : Arrays.copyOf(buf, p);}private char[][] nm(int n, int m){char[][] map = new char[n][];for(int i = 0;i < n;i++)map[i] = ns(m);return map;}private int[] na(int n){int[] a = new int[n];for(int i = 0;i < n;i++)a[i] = ni();return a;}private int ni(){int num = 0, b;boolean minus = false;while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));if(b == '-'){minus = true;b = readByte();}while(true){if(b >= '0' && b <= '9'){num = num * 10 + (b - '0');}else{return minus ? -num : num;}b = readByte();}}private long nl(){long num = 0;int b;boolean minus = false;while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-'));if(b == '-'){minus = true;b = readByte();}while(true){if(b >= '0' && b <= '9'){num = num * 10 + (b - '0');}else{return minus ? -num : num;}b = readByte();}}private static void tr(Object... o) { System.out.println(Arrays.deepToString(o)); }}