Submission #1093832

#	Time	Username	Problem	Language	Result	Execution time	Memory
1093832		Tymond	A Difficult(y) Choice (BOI21_books)	C++17	20 / 100	154 ms	1028 KiB

books

#include <bits/stdc++.h>
#include "books.h"
using namespace std;
using ll = long long;
using ld = long double;
#define fi first
#define se second
#define vi vector<int>
#define vll vector<long long>
#define pii pair<int, int>
#define pll pair<long long, long long>
#define pb push_back
#define mp make_pair
#define eb emplace_back
#define all(x) (x).begin(), (x).end()
#define sz(x) (int)(x).size()
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rng64(chrono::steady_clock::now().time_since_epoch().count());
inline int rand(int l,int r){return uniform_int_distribution<int>(l, r)(rng);}
inline ll rand(ll l,ll r){return uniform_int_distribution<ll>(l, r)(rng64);}
#ifdef DEBUG
auto&operator<<(auto&o,pair<auto,auto>p){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(auto&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<","+!i++<<e;return o<<"}";}
#define debug(X...)cerr<<"["#X"]: ",[](auto...$){((cerr<<$<<"; "),...)<<endl;}(X)
#else
#define debug(...){}
#endif
 
struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        x += 0x9e3779b97f4a7c15;
        x = (x ^ (x >> 30)) * 0xbf58476d1ce4e5b9;
        x = (x ^ (x >> 27)) * 0x94d049bb133111eb;
        return x ^ (x >> 31);
    }
 
    size_t operator()(uint64_t x) const {
        static const uint64_t FIXED_RANDOM = chrono::steady_clock::now().time_since_epoch().count();
        return splitmix64(x + FIXED_RANDOM);
    }
};

//
// --- Sample implementation for the task books ---
//
// To compile this program with the sample grader, place:
//     books.h books_sample.cpp sample_grader.cpp
// in a single folder and run:
//     g++ books_sample.cpp sample_grader.cpp
// in this folder.
//

const int MAXN = 1e5 + 7;
int n, k, s;
ll a[MAXN];
ll A;
map<int, ll> suma;

ll sum(int ind){
    if(suma[ind] != 0){
        return suma[ind];
    }
    ll res = 0LL;
    for(int i = ind; i >= ind - k + 1; i--){
        res += skim(i);
    }

    suma[ind] = res;
    return res;
}

void solve(int N, int K, long long nA, int S) {
    n = N;
    k = K;
    s = S;
    A = nA;
    if(s == n){
        for(int i = 1; i <= n; i++){
            a[i] = skim(i);
        }

        vi used(n + 1, 0);
        ll sum = 0LL;
        for(int i = 1; i <= k; i++){
            used[i] = 1;
            sum += a[i];
        }

        if(sum > 2 * A){
            impossible();
            return;
        }

        if(sum >= A){
            vi ans = {};
            for(int i = 1; i <= k; i++){
                ans.pb(i);
            }
            answer(ans);
            return;
        }

        for(int i = k; i >= 1; i--){
            int akt = i;
            while(akt + 1 <= n && used[akt + 1] == 0 && (ll)sum + a[akt + 1] - a[akt] <= 2 * A){
                sum = (ll)sum + a[akt + 1] - a[akt];
                used[akt] = 0;
                akt++;
                used[akt] = 1;
            }

            if(sum >= A){
                vi ans = {};
                for(int i = 1; i <= n; i++){
                    if(used[i]){
                        ans.pb(i);
                    }
                }
                answer(ans);
                return;
            }
        }
        impossible();
        return;
    }

    int l = k;
    int p = n;
    int s;
    while(l < p){
        s = (l + p) / 2;
        if(sum(s) < A){
            l = s + 1;
        }else{
            p = s;
        }
    }

    if(sum(l)){
        vi ans = {};
        for(int i = l; i >= l - k + 1; i--){
            ans.pb(i);
        }

        answer(ans);
        return;
    }
    impossible();
}

• Subtask 1: 5 / 5
• Subtask 2: 15 / 15
• Subtask 3: 0 / 10
• Subtask 4: 0 / 15
• Subtask 5: 0 / 15
• Subtask 6: 0 / 20
• Subtask 7: 0 / 20