Submission #1093845

#	Time	Username	Problem	Language	Result	Execution time	Memory
1093845		Tymond	A Difficult(y) Choice (BOI21_books)	C++17	45 / 100	1 ms	456 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;
ll a[MAXN];
ll A;

ll Get(int ind){
    if(a[ind] != 0){
        return a[ind];
    }
    a[ind] = skim(ind);
    return a[ind];
}

void solve(int N, int K, long long nA, int S) {
    n = N;
    k = K;
    A = nA;

    for(int i = 1; i < k; i++){
        Get(i);
    }

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

    ll sum = 0LL;
    if(Get(l) > A){
        sum = Get(l);
        vi ans = {l};
        for(int i = 1; i < k; i++){
            sum += i;
            ans.pb(i);
        }

        if(sum >= A && sum <= 2 * A){
            answer(ans);
            return;
        }
        n = l - 1;
    }else{
        n = l;
    }

    if(k > n){
        impossible();
        return;
    }

    Get(k);
    sum = 0LL;
    vi ans = {};
    for(int i = 1; i <= k; i++){
        sum += Get(i);
        ans.pb(i);
    }

    if(sum >= A && sum <= 2 * A){
        answer(ans);
        return;
    }

    for(int j = 2; j <= k + 1; j++){
        sum = 0LL;
        ans.clear();
        for(int i = j; i <= k; i++){
            ans.pb(i);
            sum += Get(i);
        }

        for(int i = n - k + 1; i <= n - k + j - 1; i++){
            ans.pb(i);
            sum += Get(i);
        }

        if(sum >= A && sum <= 2 * A){
            answer(ans);
            return;
        }
    }

    impossible();
}

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