結果

問題 No.1079 まお
ユーザー uwiuwi
提出日時 2020-06-12 21:50:08
言語 Java21
(openjdk 21)
結果
AC  
実行時間 1,002 ms / 2,000 ms
コード長 5,017 bytes
コンパイル時間 6,804 ms
コンパイル使用メモリ 82,480 KB
実行使用メモリ 81,996 KB
最終ジャッジ日時 2023-09-06 10:13:40
合計ジャッジ時間 20,428 ms
ジャッジサーバーID
（参考情報） 		judge13 / judge12
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 38 ms
49,200 KB
testcase_01 AC 37 ms
49,404 KB
testcase_02 AC 37 ms
47,164 KB
testcase_03 AC 37 ms
49,560 KB
testcase_04 AC 48 ms
50,032 KB
testcase_05 AC 63 ms
52,572 KB
testcase_06 AC 83 ms
53,104 KB
testcase_07 AC 88 ms
54,796 KB
testcase_08 AC 75 ms
54,012 KB
testcase_09 AC 88 ms
55,616 KB
testcase_10 AC 89 ms
55,192 KB
testcase_11 AC 88 ms
55,280 KB
testcase_12 AC 534 ms
76,280 KB
testcase_13 AC 537 ms
74,624 KB
testcase_14 AC 648 ms
72,228 KB
testcase_15 AC 702 ms
81,244 KB
testcase_16 AC 838 ms
80,820 KB
testcase_17 AC 881 ms
79,476 KB
testcase_18 AC 837 ms
78,080 KB
testcase_19 AC 718 ms
78,100 KB
testcase_20 AC 903 ms
78,968 KB
testcase_21 AC 895 ms
80,168 KB
testcase_22 AC 768 ms
75,620 KB
testcase_23 AC 805 ms
75,344 KB
testcase_24 AC 1,002 ms
76,524 KB
testcase_25 AC 713 ms
74,840 KB
testcase_26 AC 835 ms
81,996 KB
testcase_27 AC 216 ms
58,548 KB
testcase_28 AC 647 ms
77,288 KB
testcase_29 AC 592 ms
72,612 KB
testcase_30 AC 592 ms
70,592 KB
testcase_31 AC 304 ms
61,744 KB
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ソースコード

diff # 

package contest200612;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.HashMap;
import java.util.InputMismatchException;
import java.util.Map;

public class D {
	InputStream is;
	PrintWriter out;
	String INPUT = "";
	
	void solve()
	{
		int n = ni(), K = ni();
		int[] a = na(n);
		ans = 0;
		dfs(0, n, a, K);
		out.println(ans);
	}
	
	int[][] go(int s, int t, int[] a)
	{
		int step = s < t ? 1 : -1;
		int[][] mins = new int[2][Math.abs(t-s)];
		int p = 0;
		int min1 = Integer.MAX_VALUE, min2 = Integer.MAX_VALUE;
		for(int i = s;i != t;i += step, p++){
			if(a[i] < min1){
				min2 = min1;
				min1 = a[i];
			}else if(a[i] < min2){
				min2 = a[i];
			}
			mins[0][p] = min1;
			mins[1][p] = min2;
		}
		return mins;
	}
	
	long ans;
	
	void dfs(int l, int r, int[] a, int K)
	{
		if(r-l == 1){
			if(a[l] * 2 == K){
				ans += 1;
			}
			return;
		}
		int h = l+r>>1;
		int[][] L = go(h-1, l-1, a);
		int[][] R = go(h, r, a);
		
		// a<b<c<d
		
		// aa b* NG
		// ab b* OK
		// a* a* NG
		// bc aa NG
		// bc a* OK
		
		{
			Map<Integer, Long> maps = new HashMap<>(); 
			Map<Integer, Integer> mapc = new HashMap<>(); 
			int rp = h;
			for(int i = 0, x = h-1;i < L[0].length;i++, x--){
				while(rp < r && R[0][rp-h] > L[0][i]){
					inc(a[rp], rp-h+1, maps);
					inc(a[rp], mapc);
					rp++;
				}
				if(L[0][i] < L[1][i]){
					ans += maps.getOrDefault(K-a[x], 0L) + (long)(i+1) * mapc.getOrDefault(K-a[x], 0);
				}
			}
		}
		{
			Map<Integer, Long> maps = new HashMap<>(); 
			Map<Integer, Integer> mapc = new HashMap<>(); 
			int lp = h-1;
			for(int i = 0, x = h;i < R[0].length;i++, x++){
				while(lp >= l && L[0][h-1-lp] > R[0][i]){
					inc(a[lp], h-lp, maps);
					inc(a[lp], mapc);
					lp--;
				}
				if(R[0][i] < R[1][i]){
					ans += maps.getOrDefault(K-a[x], 0L) + (long)(i+1) * mapc.getOrDefault(K-a[x], 0);
				}
			}
		}
		dfs(l, h, a, K);
		dfs(h, r, a, K);
	}
	
	public static <T> void inc(T key, Map<T, Integer> map){inc(key, 1, map);}
	public static <T> void inc(T key, int inc, Map<T, Integer> map){map.put(key, map.getOrDefault(key, 0) + inc);}
	public static <T> void inc(T key, long inc, Map<T, Long> map){map.put(key, map.getOrDefault(key, 0L) + inc);}

	
	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 D().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)); }
}
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