#231380 (Java21) No.121 傾向と対策：門松列（その２）

• 問題: No.121 傾向と対策：門松列（その２）
• ユーザー: yuya178
• 提出日時: 2018-01-22 19:50:30
• 言語: Java21 (openjdk 21)
• 結果: TLE
• 実行時間: -
• コード長: 5,809 bytes
• コンパイル時間: 2,644 ms
• コンパイル使用メモリ: 82,276 KB
• 実行使用メモリ: 280,392 KB
• 最終ジャッジ日時: 2024-06-07 17:39:30
• 合計ジャッジ時間: 16,114 ms
• ジャッジサーバーID （参考情報）: judge1 / judge3

入力	結果	実行時間; 実行使用メモリ
testcase_00	AC	931 ms; 181,740 KB
testcase_01	AC	1,123 ms; 188,968 KB
testcase_02	AC	636 ms; 170,404 KB
testcase_03	AC	2,006 ms; 280,392 KB
testcase_04	TLE	-
testcase_05	--	-
testcase_06	--	-
testcase_07	--	-
testcase_08	--	-

ソースコード

import java.io.*;
import java.util.*;
import java.math.*;
// import java.awt.Point;
 
public class Main {
    InputStream is;
    PrintWriter out;
    String INPUT = "";
 
    long MOD = 1_000_000_007;
    long inf = Long.MAX_VALUE;

    void solve(){
        int n = ni();
        int[] a = new int[n];
        int[] b = new int[n];
        for(int i = 0; i < n; i++){
            a[i] = ni();
            b[i] = a[i];
        }
        Arrays.sort(b);
        Map<Integer,Integer> map = new HashMap<>();
        for(int i = 0; i < n; i++){
            if(map.containsKey(b[i])) continue;
            map.put(b[i], map.size());
        }
        SegmentTree seg = new SegmentTree();
        long[] lu = new long[n];
        long[] ld = new long[n];
        long[] ru = new long[n];
        long[] rd = new long[n];
        for(int i = 0; i < n; i++){
            int id = map.get(a[i]);
            ld[i] = seg.query(0,id);
            lu[i] = seg.query(id+1,n);
            seg.update(id, 1);
        }
        SegmentTree seg2 = new SegmentTree();
        for(int i = n-1; i >= 0; i--){
            int id = map.get(a[i]);
            rd[i] = seg2.query(0,id);
            ru[i] = seg2.query(id+1,n);
            seg2.update(id, 1);
        }
        long ans = 0;
        for(int i = 0; i < n; i++){
            ans += ld[i]*rd[i] + lu[i]*ru[i];
        }
        long[] R = new long[n];
        long[] L = new long[n];
        for(int i = 0; i < n; i++){
            int id = map.get(a[i]);
            R[id]++;
        }
        long res = 0;
        for(int i = 0; i < n; i++){
            int id = map.get(a[i]);
            res -= L[id]*R[id];
            ans -= res;
            R[id]--;
            L[id]++;
            res += L[id]*R[id];
        }
        out.println(ans);
    }

    class SegmentTree {
        int SIZE = 1 << 20;
        long[][] seg;
        SegmentTree() {
            this.seg = new long[2 * SIZE][1];
            for(int i=0;i<2*SIZE;++i){
                seg[i][0] = 0;
            }
        }
        long comb(long ans1, long ans2){
            return ans1+ans2;
        }
        void update(int x, long value) {
            x += SIZE - 1;
            this.seg[x][0] += value;
            while (x > 0) {
                x = (x - 1) / 2;
                this.seg[x][0] = comb(this.seg[2 * x + 1][0], this.seg[2 * x + 2][0]);
            }
        }
        long query(int a,int b,int l,int r,int k){
            if(a<=l&&r<=b) return seg[k][0];
            if(b<=l||r<=a) return 0;
            long ans1=query(a,b,l,(l+r)/2,2*k+1);
            long ans2=query(a,b,(l+r)/2,r,2*k+2);
            return comb(ans1, ans2);
        }
        long query(int l, int r) {
            return query(l,r,0,SIZE,0);
        }
    }

    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 Main().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) && 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)); }
 
}