Submission #839469

#	Time	Username	Problem	Language	Result	Execution time	Memory
839469		abysmal	Abracadabra (CEOI22_abracadabra)	C++14	100 / 100	500 ms	49568 KiB

Main

#include<iostream>
#include<stdio.h>
#include<stdint.h>
#include<iomanip>
#include<algorithm>
#include<utility>
#include<vector>
#include<stack>
#include<queue>
#include<set>
#include<map>
#include<deque>
#include<math.h>
#include<assert.h>
#include<string.h>
#include<ext/pb_ds/tree_policy.hpp>
#include<ext/pb_ds/assoc_container.hpp>

using namespace std;

const int64_t INF = (int64_t) 1e18 + 100;
const int64_t mINF = (int64_t) 1e9 + 100;
const int64_t MOD = 1e9 + 19972207;
const int64_t MOD2 = 998244353;
const int nbit = 31;
const int ndig = 10;
const int nchar = 26;
const int D = 4;
int dr[D] = {-1, 0, 1, 0};
int dc[D] = {0, 1, 0, -1};
const int Dk = 8;
int drk[Dk] = {2, 2, -2, -2, 1, 1, -1, -1};
int dck[Dk] = {1, -1, 1, -1, 2, -2, 2, -2};

struct Query
{
    int t;
    int k;
    int id;

    Query(int t_, int k_, int id_) : t(t_), k(k_), id(id_) {}

    bool operator < (const Query& o) const
    {
        if(t != o.t) return t < o.t;
        if(k != o.k) return k < o.k;
        return id < o.id;
    }
};

struct Thing
{
    int val;
    int l;
    int r;

    Thing(int val_, int l_, int r_) : val(val_), l(l_), r(r_) {}

    bool operator < (const Thing& o) const
    {
        if(val == o.val)
        {
            if(l == o.l) return r < o.r;
            return l < o.l;
        }
        return val < o.val;
    }
};

struct Solution
{
    int n;
    int m;
    int q;
    int sz;
    set<Thing> st;
    vector<int> a;
    vector<int> nx;
    vector<Query> v;
    vector<int> tree;
    vector<int> ans;
    Solution() {}

    void solve()
    {
        cin >> n >> q;
        a.resize(n, 0);
        nx.resize(n, n - 1);
        vector<int> pos(n, -1);
        for(int i = 0; i < n; i++)
        {
            cin >> a[i];
            a[i]--;
            pos[a[i]] = i;
        }

        for(int i = 0; i < q; i++)
        {
            int t;
            int k;
            cin >> t >> k;
            t = min(t, n);
            v.push_back(Query(t, k, i));
        }
        sort(v.begin(), v.end());

        m = n;
        sz = 0;
        while(__builtin_popcount(m) != 1) m++;
        tree.resize(2 * m, 0);
        stack<int> s;
        for(int i = 0; i < n; i++)
        {
            while(!s.empty() && a[s.top()] < a[i])
            {
                nx[s.top()] = i - 1;
                s.pop();
            }

            s.push(i);
        }

        int j = 0;
        ans.resize(q, -1);
        addBlocks(0, n - 1);
        for(int i = 0; i <= n; i++)
        {
            while(j < q && v[j].t == i)
            {
                int p = n;
                int x = getAns(1, 0, m - 1, v[j].k, p);
                ans[v[j].id] = a[pos[x] + v[j].k - p - 1] + 1;
                j++;
            }

            deleteRight();
            if(sz > n / 2)
            {
                Thing mid = (*prev(st.end()));
                st.erase(mid);

                int x = mid.r - (sz - n / 2);
                update(mid.val, x - mid.l + 1);
                st.insert(Thing(mid.val, mid.l, x));
                addBlocks(x + 1, mid.r);
                sz -= (mid.r - mid.l + 1);
                sz += (x - mid.l + 1);
            }
        }

        for(int i = 0; i < q; i++)
        {
            cout << ans[i] << "\n";
        }
    }

    void deleteRight()
    {
        set<Thing>::iterator it = prev(st.end());
        do
        {
            int len = (*it).r - (*it).l + 1;
            if(sz - len < n / 2) break;

            st.erase(it);
            it = prev(st.end());
            sz -= len;
        } while(it != st.begin());
    }

    void addBlocks(int l, int r)
    {
        while(l <= r)
        {
            int e = min(nx[l], r);
            int len = e - l + 1;
            sz += len;
            st.insert(Thing(a[l], l, e));

            update(a[l], len);
            l = nx[l] + 1;
        }
    }

    int getAns(int node, int nleft, int nright, int id, int& p)
    {
        if(nleft == nright)
        {
            p -= tree[node];
            return nleft;
        }

        int mid = nleft + (nright - nleft) / 2;
        if(p - tree[node * 2 + 1] >= id)
        {
            p -= tree[node * 2 + 1];
            return getAns(node * 2, nleft, mid, id, p);
        }
        return getAns(node * 2 + 1, mid + 1, nright, id, p);
    }

    void update(int id, int val)
    {
        tree[m + id] = val;
        for(int i = (m + id) / 2; i >= 1; i /= 2)
        {
            tree[i] = tree[i * 2] + tree[i * 2 + 1];
        }
    }

    int modadd(int t1, int t2)
    {
        int res = t1 + t2;
        if(res >= MOD) res -= MOD;
        return res;
    }

    int modsub(int t1, int t2)
    {
        int res = t1 - t2;
        if(res < 0) res += MOD;
        return res;
    }

    int modmul(int t1, int t2)
    {
        int64_t res = 1LL * t1 * t2;
        return res % MOD;
    }

    int Abs(int tmp)
    {
        if(tmp < 0) return -tmp;
        return tmp;
    }

    int MASK(int j)
    {
        return (1 << j);
    }

    bool BIT(int tmp, int j)
    {
        return (tmp & MASK(j));
    }
};

void __setup()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL); cout.tie(NULL);

//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
}

int main()
{
    __setup();

    int t = 1;
//    cin >> t;
    for(int i = 1; i <= t; i++)
    {
        Solution().solve();
    }
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 40 / 40
• Subtask 3: 25 / 25
• Subtask 4: 25 / 25