Submission #1196163

#	Time	Username	Problem	Language	Result	Execution time	Memory
1196163		countless	Boxes with souvenirs (IOI15_boxes)	C++20	10 / 100	0 ms	332 KiB

boxes

#include "boxes.h"
#include <bits/stdc++.h>
using namespace std;

typedef long long ll;
typedef long double ld;

const ll MOD = 998244353;
const ll INF = 1e18;
const ld EPS = 1e-12;

#define endl "\n"
#define sp <<" "<<
#define REP(i, a, b) for(ll i = a; i < b; i++)
#define dbg(x) cout << #x << " = " << x << endl
#define mp make_pair
#define pb push_back
#define fi first
#define se second
#define fast_io() ios_base::sync_with_stdio(false); cin.tie(NULL)
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define sz(x) ((ll)(x).size())

struct custom_hash {
    static uint64_t splitmix64(uint64_t x) {
        // http://xorshift.di.unimi.it/splitmix64.c
        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);
    }
};

template <typename Key, typename Value>
using hash_map = unordered_map<Key, Value, custom_hash>;

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
// uniform_int_distribution<int>(a, b)(rng);
// shuffle(all(a), rng);

ll delivery(int N, int K, int L, int p[]) {
    vector<ll> left, right;

    auto work = [&](int x) -> void {
        if (x == 0)
            return;

        if (x < L - x) {
            left.push_back(2LL * x);
        } else {
            right.push_back(2LL * (L - x));
        }
    };

    REP(i, 0, N) {
        work(p[i]);
    }

    sort(all(left)), sort(all(right));

    auto fix = [&](vector<ll> &a) -> void {
        // add by k's
        for (int i = K; i < a.size(); i++) {
            a[i] += a[i - K];
        }
    };

    fix(left), fix(right);

    // trav left then trav right
    ll ans = (left.size() ? *left.rbegin() : 0) +
            (right.size() ? *right.rbegin() : 0);

    // sliding window
    vector<int> comb;
    comb.insert(comb.end(), all(left));
    comb.insert(comb.end(), rall(right));

    // groups of last k
    int l, r; l = max(0, int(left.size() - K)), r = l + K - 1;

    auto find = [&]() -> void {
        ll res = L;
        ll resLeft = (l > 0) ? comb[l-1] : 0;
        ll resRight = (r + 1 < N) ? comb[r+1] : 0;
        res += resLeft + resRight;

        ans = min(ans, res);
    };

    if (left.size() and right.size()) {
        while (l < left.size()) {
            find();
            l++, r++;
        }
    }

    return ans;
}

// signed main() {
//     int n, k, l; cin >> n >> k >> l;
//     int p[n];
//     REP(i, 0, n) cin >> p[i];
//     cout << delivery(n, k, l, p) << endl;
// }

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 15
• Subtask 5: 0 / 20
• Subtask 6: 0 / 30