Submission #530474

#	Time	Username	Problem	Language	Result	Execution time	Memory
530474		KoD	Swap (BOI16_swap)	C++17	68 / 100	1037 ms	262148 KiB

swap

#include <bits/stdc++.h>

using std::vector;
using std::array;
using std::tuple;
using std::pair;

template <class F> struct rec_lambda : private F {
    explicit rec_lambda(F&& f) : F(std::forward<F>(f)) {}
    template <class... Args> decltype(auto) operator()(Args&&... args) const {
        return F::operator()(*this, std::forward<Args>(args)...);
    }
};

vector<int> merge(const int top, const vector<int>& l, const vector<int>& r) {
    const int n = l.size(), m = r.size();
    vector<int> ret;
    ret.reserve(1 + n + m);
    ret.push_back(top);
    int i = 0, j = 1;
    while (i < n or i < m) {
        for (int k = i; k < i + j and k < n; ++k) {
            ret.push_back(l[k]);
        }
        for (int k = i; k < i + j and k < m; ++k) {
            ret.push_back(r[k]);
        }
        i += j;
        j <<= 1;
    }
    return ret;
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    
    int N;
    std::cin >> N;
    vector<int> X(N);
    for (auto& x : X) {
        std::cin >> x;
    }

    std::map<long long, vector<int>> dp;
    const auto code = [&](const int root, const int top) {
        return ((long long)root << 18) + top;
    };

    const auto ans = rec_lambda([&](auto&& dfs, const int root, const int top) -> vector<int> {
        auto& ret = dp[code(root, top)];
        if (!ret.empty()) {
            return ret;
        }
        const int lch = 2 * root + 1, rch = 2 * root + 2;
        if (lch >= N) {
            return ret = {top};
        }
        if (rch >= N) {
            if (top < X[lch]) {
                return ret = {top, X[lch]};
            } else {
                return ret = {X[lch], top};
            }
        }
        int a = top, b = X[lch], c = X[rch];
        if (a < b and a < c) {
            return ret = merge(a, dfs(lch, b), dfs(rch, c));
        }
        if (b < a and b < c) {
            return ret = merge(b, dfs(lch, a), dfs(rch, c));
        }
        return ret = std::min(merge(c, dfs(lch, a), dfs(rch, b)), merge(c, dfs(lch, b), dfs(rch, a)));
    })(0, X[0]);

    for (int i = 0; i < N; ++i) {
        std::cout << ans[i] << " \n"[i + 1 == N];
    }

    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 11 / 11
• Subtask 3: 27 / 27
• Subtask 4: 20 / 20
• Subtask 5: 0 / 32