#466545 (Java) No.1031 いたずら好きなお姉ちゃん

• 問題: No.1031 いたずら好きなお姉ちゃん
• ユーザー: uwi
• 提出日時: 2020-04-18 16:16:33
• 言語: Java (openjdk 23)
• 結果: WA
• 実行時間: -
• コード長: 7,161 bytes
• コンパイル時間: 4,211 ms
• コンパイル使用メモリ: 84,144 KB
• 実行使用メモリ: 70,104 KB
• 最終ジャッジ日時: 2024-10-03 23:52:38
• 合計ジャッジ時間: 23,806 ms
• ジャッジサーバーID （参考情報）: judge1 / judge4

ファイルパターン	結果
sample	WA * 3
other	AC * 2 WA * 51

ソースコード

package contest200417;
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 E3 {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		int n = ni();
		int[] a = na(n);
		
		out.println(go(a) + go(rev(a)));
	}
	
	public static int[] rev(int[] a){int[] b = new int[a.length];for(int i = 0;i < a.length;i++)b[a.length-1-i] = a[i];return b;}

	
	long go(int[] a)
	{		
		int n = a.length;
		int[] larger = enumPrevWall(a);
		int[] smaller = enumPrevShutter(a);
		int[] par = new int[n+1];
		for(int i = 0;i < n;i++){
			par[i] = larger[i] == -1 ? n : larger[i];
		}
		par[n] = -1;
		int[][] g = parentToG(par);
		
		int[][] pars = parents3(g, n);
		int[] dep = pars[2];
		
		int[][] qs = new int[n][];
		
		long ans = 0;
		int p = 0;
		for(int i = 0;i < n;i++){
			int s = smaller[i];
			if(s != -1)qs[p++] = new int[]{i, smaller[i], -1};
			
			ans += dep[i];
		}
		ans -= n;
		int[] rets = offlineLCA(g, Arrays.copyOf(qs, p), n);
		for(int i = 0;i < p;i++){
			ans -= rets[i];
		}
		
		return ans;
	}
	
	public static int[] offlineLCA(int[][] g, int[][] qs, int root)
	{
		int n = g.length;
		DJSet ds = new DJSet(n);
		int[] ancs = new int[n];
		for(int i = 0;i < n;i++)ancs[i] = i;
		int Q = qs.length;
		long[][] qg = packUInd(n, qs);
		boolean[] ved = new boolean[n];
		int[] rets = new int[Q];
		Arrays.fill(rets, -1);
		int[] stack = new int[n+1];
		int[] inds = new int[n+1];
		int sp = 0;
		stack[sp++] = root;
		while(sp > 0){
			int cur = stack[sp-1];
			if(inds[sp-1] > 0 && inds[sp-1] <= g[cur].length){
				int e = g[cur][inds[sp-1]-1];
				ds.union(cur, e);
				ancs[ds.root(cur)] = cur;
			}
			if(inds[sp-1] < g[cur].length){
				int e = g[cur][inds[sp-1]];
				inds[sp-1]++;
				if(sp == 1 || e != stack[sp-2]){
					stack[sp] = e;
					inds[sp] = 0;
					sp++;
				}
				continue;
			}
			ved[cur] = true;
			for(long q : qg[cur]){
				if(ved[(int)(q>>>32)]){
					rets[(int)q] = ancs[ds.root((int)(q>>>32))];
				}
			}
			sp--;
		}
		return rets;
	}
	
	public static long[][] packUInd(int n, int[][] ft)
	{
		long[][] g = new long[n][];
		int[] p = new int[n];
		for(int[] u : ft){
			p[u[0]]++; p[u[1]]++;
		}
		for(int i = 0;i < n;i++)g[i] = new long[p[i]];
		int id = 0;
		for(int[] u : ft){
			g[u[0]][--p[u[0]]] = (long)u[1]<<32|id;
			g[u[1]][--p[u[1]]] = (long)u[0]<<32|id;
			id++;
		}
		return g;
	}
	
	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 };
	}

	
	public static int[][] parentToG(int[] par)
	{
		int n = par.length;
		int[] ct = new int[n];
		for(int i = 0;i < n;i++){
			if(par[i] >= 0){
				ct[i]++;
				ct[par[i]]++;
			}
		}
		int[][] g = new int[n][];
		for(int i = 0;i < n;i++){
			g[i] = new int[ct[i]];
		}
		for(int i = 0;i < n;i++){
			if(par[i] >= 0){
				g[par[i]][--ct[par[i]]] = i;
				g[i][--ct[i]] = par[i];
			}
		}
		return g;
	}
	

	
	
	
	public static int[] enumPrevWall(int[] a)
	{
		int n = a.length;
		int[] L = new int[n];
		L[0] = -1;
		for(int i = 1;i < n;i++){
			L[i] = i-1;
			while(L[i] >= 0 && a[L[i]] < a[i])L[i] = L[L[i]];
		}
		return L;
	}

	public static int[] enumPrevShutter(int[] a)
	{
		int n = a.length;
		int[] L = new int[n];
		L[0] = -1;
		for(int i = 1;i < n;i++){
			L[i] = i-1;
			while(L[i] >= 0 && a[L[i]] > a[i])L[i] = L[L[i]];
		}
		return L;
	}

	
	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");
//		Thread t = new Thread(null, null, "~", Runtime.getRuntime().maxMemory()){
//			@Override
//			public void run() {
//				long s = System.currentTimeMillis();
//				solve();
//				out.flush();
//				if(!INPUT.isEmpty())tr(System.currentTimeMillis()-s+"ms");
//			}
//		};
//		t.start();
//		t.join();
	}
	
	public static void main(String[] args) throws Exception { new E3().run(); }
	
	private byte[] inbuf = new byte[1024];
	public 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 int[] na(int n)
	{
		int[] a = new int[n];
		for(int i = 0;i < n;i++)a[i] = ni();
		return a;
	}
	
	private long[] nal(int n)
	{
		long[] a = new long[n];
		for(int i = 0;i < n;i++)a[i] = nl();
		return a;
	}
	
	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[][] nmi(int n, int m) {
		int[][] map = new int[n][];
		for(int i = 0;i < n;i++)map[i] = na(m);
		return map;
	}
	
	private int ni() { return (int)nl(); }
	
	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)); }
}