Submission #310196

#	Time	Username	Problem	Language	Result	Execution time	Memory
310196		hhoangcpascal	Holiday (IOI14_holiday)	C++14	100 / 100	250 ms	44332 KiB

holiday

/// hhoangcpascal

#include <cstdio>
#include <iostream>
#include <algorithm>
#include <vector>
#define file_name "Holiday"
#define llong long long

using namespace std;

struct TNode {
    int Left, Right;
    int cnt;
    llong sum;
} Seg[1800006];

int Time = 0, sz, Start, n, d, root[100006], a[100006], sorted[100006];

void Compress() {
    sort(sorted+1, sorted+n+1);
    sz = unique(sorted+1, sorted+n+1) - sorted - 1;

    for(int i=1; i<=n; ++i) a[i] = lower_bound(sorted+1, sorted+sz+1, a[i]) - sorted;
}

void Update(int old, int ver, int l, int r, int x, int val) {
    if (l > x || r < x || l > r) return;
    if (l == r) {
        Seg[ver].sum = Seg[old].sum + 1LL * val * sorted[l];
        Seg[ver].cnt = Seg[old].cnt + val;
        return;
    }

    int mid = (l + r) >> 1;
    if (x <= mid) {
        Seg[ver].Right = Seg[old].Right;
        Seg[ver].Left = ++Time;
        Update(Seg[old].Left, Seg[ver].Left, l, mid, x, val);
    } else {
        Seg[ver].Left = Seg[old].Left;
        Seg[ver].Right = ++Time;;
        Update(Seg[old].Right, Seg[ver].Right, mid+1, r, x, val);
    }

    Seg[ver].cnt = Seg[Seg[ver].Left].cnt + Seg[Seg[ver].Right].cnt;
    Seg[ver].sum = Seg[Seg[ver].Left].sum + Seg[Seg[ver].Right].sum;
}

llong Get(int old, int ver, int l, int r, int cnt) {
    if (cnt <= 0) return 0LL;
    if (l == r) return 1LL * cnt * sorted[l];

    int mid = (l + r) >> 1;
    int tmp = Seg[Seg[ver].Right].cnt - Seg[Seg[old].Right].cnt;

    llong ans;
    if (tmp > cnt) ans = Get(Seg[old].Right, Seg[ver].Right, mid+1, r, cnt);
    else {
        ans = Seg[Seg[ver].Right].sum - Seg[Seg[old].Right].sum;
        ans += Get(Seg[old].Left, Seg[ver].Left, l, mid, cnt - tmp);
    }

    return ans;
}

llong res = 0;

void DAC(int l, int r, int u, int v) {
    if (l > r) return;

    int mid = (l + r) >> 1, p = u;
    llong tmp = -1;

    for(int i=u; i<=v; ++i) {
        int len_l = Start - mid, len_r = i - Start;
        int cnt = d - len_l - len_r - min(len_l, len_r);
        cnt = min(cnt, i - mid + 1);
        if (cnt < 0) continue;
        llong now = Get(root[mid-1], root[i], 1, sz, cnt);

        if (tmp < now) {
            tmp = now;
            p = i;
        }
    }

    res = max(res, tmp);
    DAC(l, mid - 1, u, p);
    DAC(mid + 1, r, p, v);
}

llong findMaxAttraction(int N, int St, int D, int arr[]) {
    n = N, Start = St + 1, d = D;
    for(int i=n; i>0; --i) a[i] = sorted[i] = arr[i-1];
    Compress();

    for(int i=1; i<=n; ++i) {
        root[i] = ++Time;
        Update(root[i-1], root[i], 1, sz, a[i], 1);
    }

    DAC(1, Start, Start, n);
    return res;
}

• Subtask 1: 7 / 7
• Subtask 2: 23 / 23
• Subtask 3: 17 / 17
• Subtask 4: 53 / 53