Submission #654042

#	Time	Username	Problem	Language	Result	Execution time	Memory
654042		Vladth11	Abracadabra (CEOI22_abracadabra)	C++14	100 / 100	756 ms	35032 KiB

Main

#include <iostream>
#include <vector>
#include <algorithm>
 
#pragma GCC optimize("Ofast")
 
#define debug(x) cerr << #x << " " << x << "\n"
#define debugs(x) cerr << #x << " " << x << " "
 
using namespace std;
typedef long long ll;
typedef pair <int, int> pii;
 
const int bSize = 11;
const int bits = 17;
const int NMAX = 200001;
const int LIMIT = NMAX;
 
vector <pii> qq[LIMIT + 1];
int sol[NMAX * 5];
int v[NMAX];
int poz[NMAX];
int stiva[NMAX];
int vf;
int nxt[NMAX];
pii interval[NMAX];
int aib[NMAX];
 
void update(int node, int x) {
    for(; node < NMAX; node += node&(-node))
        aib[node] += x;
}
 
int query(int node) {
    int x = 0;
    for(; node > 0; node -= node&(-node))
        x += aib[node];
    return x;
}
 
int cb(int k){
    int r = 0, pas = (1 << bits), sum = 0;
    while(pas){
        if(r + pas < NMAX && aib[r + pas] + sum < k){
            sum += aib[r + pas];
            r += pas;
        }
        pas /= 2;
    }
    if(sum < k)
        r++;
    return r;
}
 
 
int sz(pii x) {
    if(x.second == 0)
        return 0;
    return x.second - x.first + 1;
}
 
int n;
 
void mShuffle() {
    int cine = cb(n / 2);
    if(query(cine) == n / 2) {
        return;
    }
    int dr = interval[cine].second;
    update(cine, -sz(interval[cine]));
    int pana = query(cine - 1);
    int node = n / 2;
    node -= pana;
    interval[cine] = {poz[cine], poz[cine] + node - 1};
    update(cine, sz(interval[cine]));
    int i = v[poz[cine] + node];
    while(sz(interval[i]) == 0 && poz[i] <= dr) {
        int urm = nxt[poz[i]];
        if(urm == 0)
            urm = n + 1;
        urm = min(urm, dr + 1);
        interval[i] = {poz[i], urm - 1};
        update(i, sz(interval[i]));
        if(urm != n + 1)
            i = v[urm];
    }
}
 
int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    int q, i;
    cin >> n >> q;
    for(i = 1; i <= n; i++) {
        cin >> v[i];
        poz[v[i]] = i;
        while(vf && v[stiva[vf]] < v[i]) {
            nxt[stiva[vf]] = i;
            vf--;
        }
        stiva[++vf] = i;
    }
    i = 1;
    while(nxt[i] != 0) {
        interval[v[i]] = {i, nxt[i] - 1};
        i = nxt[i];
    }
    interval[v[i]] = {i, n};
    for(i = 1; i <= n; i++) {
        update(i, sz(interval[i]));
    }
    for(i = 1; i <= q; i++) {
        int x, y;
        cin >> x >> y;
        x = min(x, LIMIT);
        qq[x].push_back({y, i});
    }
    for(i = 0; i <= LIMIT; i++) {
        for(auto x : qq[i]) {
            int node = x.first;
            int idx = x.second;
            int cine = cb(node);
            int pana = query(cine - 1);
            node -= pana;
            sol[idx] = v[poz[cine] + node - 1];
        }
        mShuffle();
    }
    for(i = 1; i <= q; i++) {
        cout << sol[i] << "\n";
    }
    return 0;
}

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