Submission #341038

#	Time	Username	Problem	Language	Result	Execution time	Memory
341038		12tqian	Boxes with souvenirs (IOI15_boxes)	C++17	100 / 100	655 ms	93620 KiB

boxes

#include "boxes.h"
#include <bits/stdc++.h>
typedef long long ll;
const ll INF = 1e18;
struct MinDeque {
    int lo = 0, hi = -1;
    std::deque<std::pair<ll, int>> d;
    void ins(ll x) { // add to back
        while ((d).size() && d.back().first >= x) d.pop_back();
        d.push_back({x, ++hi});
    }
    void del() { // delete from front
        if (d.front().second == lo++) d.pop_front();
    }
    ll get() {
        return (d).size() ? d.front().first : INF;
    }
};

long long delivery(int N, int K, int L, int p[]) {
    using namespace std;
    ll ans = INF;
    MinDeque D1;
    MinDeque D2;
    D1.ins(0);
    D2.ins(2 * (L-p[0]));
    for (int i = 0; i < N; i++) {
        ll res = INF;
        res = min(res, D2.get());
        res = min(res, D1.get() + min(L, 2*p[i]));
        if (i != N-1) {
            D1.ins(res);
            D2.ins(res+2*L-2*p[i+1]);
        }
        if (i >= K-1 && i != N-1) {
            D1.del();
            D2.del();
        }
        if (i == N-1) ans = res;
    }
    return ans;
}

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