Submission #189151

#	Time	Username	Problem	Language	Result	Execution time	Memory
189151		Nicksechko	DEL13 (info1cup18_del13)	C++17	100 / 100	21 ms	3764 KiB

del13

#include <vector>
#include <iostream>
#include <algorithm>
#include <functional>

using namespace std;

const int inf = 1'000'000'088;

template<typename T>
T& InplaceMin(T& a, const T& b) {
    return a = min(a, b);
}

void Solve(istream& in, ostream& out) {
    int n, q;
    in >> n >> q;

    vector<int> p(q + 2);
    p[q + 1] = n + 1;
    for (int i = 1; i <= q; ++i) {
        in >> p[i];
    }

    vector<vector<pair<int, int>>> dp(q + 2, vector<pair<int, int>>(3, make_pair(inf, inf)));

    function<pair<int, int>(int, int, int, int)> update =
        [&dp](int i, int from, int to, int delta) {
            return InplaceMin(dp[i + 1][to], make_pair(dp[i][from].first + delta, from));
        };

    dp[0][0].first = 0;
    for (int i = 0; i <= q; ++i) {
        int cnt = p[i + 1] - p[i] - 1;
        for (int j = 0; j <= min(cnt, 2); j++) {
            if (dp[i][j].first == inf) {
                continue;
            }
            if (cnt == j) {
                update(i, j, 0, 0);
                continue;
            }
            if ((j + cnt) % 2 == 0) {
                if (j != 0) {
                    update(i, j, 0, (cnt - j) / 2);
                }
                update(i, j, 2, (cnt - j) / 2 + 1);
            } else {
                update(i, j, 1, (cnt - j) / 2 + 1);
            }
        }
    }

    if (dp[q + 1][0].first == inf) {
        out << -1 << endl;
        return;
    }

    vector<int> ans;
    int cur = 0;
    for (int i = q; i >= 0; --i) {
        int prev = dp[i + 1][cur].second;
        int first = p[i] + 2 + prev;
        if (cur == 0) {
            for (int j = 0; j < prev; ++j) {
                ans.push_back(p[i]);
            }
            first -= prev;
        }
        for (int j = first; j + 1 < p[i + 1]; j += 2) {
            ans.push_back(j);
        }
        if (cur != 0) {
            for (int j = 0; j < prev; ++j) {
                ans.push_back(p[i]);
            }
        }
        cur = prev;
    }
    reverse(ans.begin(), ans.end());

    out << ans.size() << endl;
    for (auto& item : ans) {
        out << item << " ";
    }
    out << endl;
}

int main() {
    std::ios_base::sync_with_stdio(false);

    int t;
    cin >> t;
    while (t--) {
        Solve(cin, cout);
    }
    return 0;
}

• Subtask 1: 15 / 15
• Subtask 2: 15 / 15
• Subtask 3: 15 / 15
• Subtask 4: 25 / 25
• Subtask 5: 30 / 30