Submission #409621

#	Time	Username	Problem	Language	Result	Execution time	Memory
409621		KoD	Jakarta Skyscrapers (APIO15_skyscraper)	C++17	22 / 100	1094 ms	588 KiB

skyscraper

#include <bits/stdc++.h>

using i32 = std::int32_t;
using u32 = std::uint32_t;
using i64 = std::int64_t;
using u64 = std::uint64_t;
using i128 = __int128_t;
using u128 = __uint128_t;
using isize = std::ptrdiff_t;
using usize = std::size_t;

class rep {
    struct Iter {
        usize itr;
        constexpr Iter(const usize pos) noexcept : itr(pos) {}
        constexpr void operator++() noexcept { ++itr; }
        constexpr bool operator!=(const Iter& other) const noexcept { return itr != other.itr; }
        constexpr usize operator*() const noexcept { return itr; }
    };
    const Iter first, last;

  public:
    explicit constexpr rep(const usize first, const usize last) noexcept : first(first), last(std::max(first, last)) {}
    constexpr Iter begin() const noexcept { return first; }
    constexpr Iter end() const noexcept { return last; }
};

template <class T, T Div = 2> constexpr T INFTY = std::numeric_limits<T>::max() / Div;

template <class T> bool setmin(T& lhs, const T& rhs) {
    if (lhs > rhs) {
        lhs = rhs;
        return true;
    }
    return false;
}

template <class T> using Vec = std::vector<T>;

template <class T> using Heap = std::priority_queue<T, Vec<T>, std::greater<T>>;

void main_() {
    usize N, M;
    std::cin >> N >> M;
    Vec<usize> B(M), P(M);
    Vec<Vec<usize>> lives(N);
    for (const auto i : rep(0, M)) {
        std::cin >> B[i] >> P[i];
        lives[B[i]].push_back(i);
    }
    Vec<std::array<u64, 150>> dist(N);
    for (auto& v : dist) {
        v.fill(INFTY<u64>);
    }
    Heap<std::tuple<u64, usize, usize>> heap;
    const auto push = [&](const usize u, const usize k, const u64 d) {
        if (setmin(dist[u][k], d)) {
            heap.emplace(d, u, k);
        }
    };
    push(B[0], 0, 0);
    while (!heap.empty()) {
        const auto [d, u, k] = heap.top();
        heap.pop();
        if (dist[u][k] < d) {
            continue;
        }
        if (k != 0) {
            push(u, 0, d);
            if (u >= k) {
                push(u - k, k, d + 1);
            }
            if (u + k < N) {
                push(u + k, k, d + 1);
            }
            continue;
        }
        for (const auto x : lives[u]) {
            const auto l = P[x];
            if (l < 150) {
                push(u, l, d);
            } else {
                usize v = u;
                u64 c = d;
                while (v >= k) {
                    v -= k;
                    c += 1;
                    push(v, 0, c);
                }
                v = u;
                c = d;
                while (v + k < N) {
                    v += k;
                    c += 1;
                    push(v, 0, c);
                }
            }
        }
    }
    const auto ans = dist[B[1]][0];
    if (ans == INFTY<u64>) {
        std::cout << -1 << '\n';
    } else {
        std::cout << ans << '\n';
    }
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);
    main_();
    return 0;
}

• Subtask 1: 10 / 10
• Subtask 2: 12 / 12
• Subtask 3: 0 / 14
• Subtask 4: 0 / 21
• Subtask 5: 0 / 43