Submission #938023

#	Time	Username	Problem	Language	Result	Execution time	Memory
938023		danikoynov	Teams (IOI15_teams)	C++14	100 / 100	2388 ms	361548 KiB

teams

#include "teams.h"

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

struct segment
{
    int l, r;

    segment(int _l = 0, int _r = 0)
    {
        l = _l;
        r = _r;
    }
};

const int maxn = 5e5 + 10;

struct node
{
    node *lc, *rc;
    int sum;

    node(int _sum = 0)
    {
        lc = rc = NULL;
        sum = _sum;
    }
};

node *update(node *root, int left, int right, int pivot)
{

    if (left == right)
    {
        int val = 1;
        if (root != NULL)
            val += root -> sum;
        return new node(val);
    }

    int mid = (left + right) / 2;
    node *new_root = new node();
    if (root != NULL)
    {
        new_root -> lc = root -> lc; /// try to change this
        new_root -> rc = root -> rc;
    }

    if (pivot <= mid)
        new_root -> lc = update(new_root -> lc, left, mid, pivot);
    else
        new_root -> rc = update(new_root -> rc, mid + 1, right, pivot);

    new_root -> sum = 0;
    if (new_root -> lc != NULL)
        new_root -> sum += new_root -> lc -> sum;
    if (new_root -> rc != NULL)
        new_root -> sum += new_root -> rc -> sum;
    return new_root;
}

int query(node *root, int left, int right, int qleft, int qright)
{
    if (left > qright || right < qleft || root == NULL)
        return 0;

    if (left >= qleft && right <= qright)
        return root -> sum;

    int mid = (left + right) / 2;
    return query(root -> lc, left, mid, qleft, qright) +
           query(root -> rc, mid + 1, right, qleft, qright);
}

int n;
segment s[maxn];
node *root[maxn];
vector < int > upd[maxn];
void init(int N, int A[], int B[])
{
    n = N;
    for (int i = 1; i <= n; i ++)
    {
        s[i] = segment(A[i - 1], B[i - 1]);
        upd[A[i - 1]].push_back(B[i - 1]);
    }

    root[0] = NULL;
    for (int i = 1; i <= n; i ++)
    {
        root[i] = root[i - 1];
        for (int pivot : upd[i])
        {
            root[i] = update(root[i], 1, n, pivot);
        }
    }

    ///exit(0);
}


int zeta(int a, int b)
{
    if (a >= b)
    return 0;
    return query(root[b], 1, n, b, n) - query(root[a], 1, n, b, n);
    /**int cnt = 0;
    for (int i = 1; i <= n; i ++)
    {
        if (s[i].l <= a && s[i].r >= a)
            continue;
        if (s[i].l <= b && s[i].r >= b)
            cnt ++;
    }
    return cnt;*/
}

int pivot_change(int a, int b, int diff)
{
    /// dp_a + z(a, i) > dp_b + z(b, i)
    /// dp_b - dp_a < z(a, i) - z(b, i)
    /// diff < ....
    int lf = b, rf = n;
    while(lf <= rf)
    {
        int mf = (lf + rf) / 2;
        if (diff < zeta(a, mf) - zeta(b, mf))
            lf = mf + 1;
        else
            rf = mf - 1;
    }
    return lf;
}

int dp[maxn];
int can(int M, int K[])
{
    sort(K, K + M);
    set < int > act;
    set < pair < int, int > > event;

    for (int i = 0; i < M; i ++)
    {
        while(!event.empty() && (*event.begin()).first <= K[i])
        {
            set < int > :: iterator it = act.find((*event.begin()).second);
            event.erase({pivot_change(K[*prev(it)], K[*it], dp[*it] - dp[*prev(it)]), *it});
            if (next(it) != act.end())
            {
                event.erase({pivot_change(K[*it], K[*next(it)], dp[*next(it)] - dp[*it]), *next(it)});
                event.insert({pivot_change(K[*prev(it)], K[*next(it)], dp[*next(it)] - dp[*prev(it)]), *next(it)});
            }
            act.erase(it);
        }
        dp[i] = zeta(0, K[i]) - K[i];
        if (!act.empty())
        {
            int bk = *act.rbegin();
            dp[i] = min(dp[i], dp[bk] + zeta(K[bk], K[i]) - K[i]);
        }
        /**for (int j : act)
        {
            dp[i] = min(dp[i], dp[j] + zeta(K[j], K[i]) - K[i]);
        }*/
        if (dp[i] < 0)
            return 0;

        if (!act.empty())
        {
            int bk = *act.rbegin();
            event.insert({pivot_change(K[bk], K[i], dp[i] - dp[bk]), i});
        }
        act.insert(i);
    }
    return 1;
}

• Subtask 1: 21 / 21
• Subtask 2: 13 / 13
• Subtask 3: 43 / 43
• Subtask 4: 23 / 23