Submission #780216

#	Time	Username	Problem	Language	Result	Execution time	Memory
780216		fatemetmhr	Holiday (IOI14_holiday)	C++17	100 / 100	486 ms	5696 KiB

holiday

//  ~ Be Name Khoda ~  //

#include"holiday.h"
#include <bits/stdc++.h>
//#pragma GCC optimize ("O3")
//#pragma GCC target("avx2")
//#pragma GCC optimize("unroll-loops,Ofast")

using namespace std;

typedef long long ll;

#define pb       push_back
#define mp       make_pair
#define all(x)   x.begin(), x.end()
#define fi       first
#define se       second

const int maxn  =  1e6   + 10;
const int maxn5 =  1e6   + 10;
const int maxnt =  1.2e6 + 10;
const int maxn3 =  1e3   + 10;
const int mod   =  1e9   + 7;
const int lg    =  19;
const ll  inf   =  1e18;

vector <int> ch;
ll sum = 0, ans = 0;
int lim = 0, pt[maxn5];
int dis, st, val[maxn5];
vector <pair<int, int>> num;

struct fen{

    ll fen[maxn5];

    void add(int id, ll x){
        ////cout << "ha adding " << id << endl;
        for(; id < maxn5; id += id & -id)
            fen[id] += x;
    }

    ll get(int id){
        ////cout << "get " << id << endl;
        ll ret = 0;
        for(; id; id -= id & -id)
            ret += fen[id];
        return ret;
    }

    int find(int k){
        int ret = 0;
        for(int i = lg - 1; i >= 0; i--) 
            if(ret + (1 << i) < maxn5 && fen[ret + (1 << i)] < k){
                ret += (1 << i);
                k -= fen[ret];
            }
        return min(maxn5 - 1, ret + 1);
    }

} fen1, fen2;

void add(int id){
    //cout << "adding " << id << endl;
    ch.pb(id);
    fen1.add(pt[id], 1);
    fen2.add(pt[id], val[id]);
}


void undo(int x){
    while(ch.size() > x){
        int id = ch.back();
        ch.pop_back();
        //cout << "poping " << id << endl;
        fen1.add(pt[id], -1);
        fen2.add(pt[id], -val[id]);
    }
}

void solve(int l, int r, int optl, int optr){
    //cout << "welcome " << l << ' ' << r << ' ' << optl << ' ' << optr << ' ' << ch.size() << endl;
    int mid = (l + r) >> 1;
    int opt = optl;
    int keep = ch.size();
    ll best = -1;
    for(int i = mid; i < optl && i < r; i++)
        add(i);
    for(int i = max(mid, optl); i < optr; i++){
        add(i);
        int rem = dis - (min(abs(st - mid), abs(st - i)) + i - mid);
        if(rem < 0)
            break;
        int pt;
        ll sum;
        if(rem == 0)
            sum = 0;
        else{
            pt = fen1.find(rem);
            sum = fen2.get(pt);
        }
        //cout << mid << ' ' << i << ' ' << rem << ' ' << optl << ' ' << optr << ' ' << pt << ' ' << sum << endl;
        if(sum >= best){
            best = sum;
            opt = i;
        }
    }
    //cout << "all here " << l << ' ' << r << endl;
    ans = max(ans, best);
    undo(keep);
    if(r - l > 1){
        for(int i = mid; i < min(r, optl); i++)
            add(i);
        solve(l, mid, optl, opt + 1);
        undo(keep);
        for(int i = max(optl, r); i < opt; i++)
            add(i);
        solve(mid + 1, r, opt, optr);
    }
    ////cout << "done with " << l << ' ' << r << endl;
}

long long int findMaxAttraction(int n, int start, int d, int attraction[]){
    if(d == 0)
        return 0;
    dis = d;
    st = start;
    //ll all = 0;
    for(int i = 0; i < n; i++){
        val[i] = attraction[i];
        //all += val[i];
        num.pb({-val[i], i});
    }
    ////cout << all << endl;
    sort(all(num));
    for(int i = 0; i < n; i++)
        pt[i] = lower_bound(all(num), mp(-val[i], i)) - num.begin() + 1;
    solve(max(0, start - d), min(n, start + d + 1), max(0, start - d), min(n, start + d + 1));
    return ans;
}

Compilation message (stderr)

holiday.cpp: In function 'void undo(int)':
holiday.cpp:72:21: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   72 |     while(ch.size() > x){
      |           ~~~~~~~~~~^~~

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