Submission #1294575

#	Time	Username	Problem	Language	Result	Execution time	Memory
1294575		MisterReaper	Tortoise (CEOI21_tortoise)	C++20	48 / 100	3117 ms	573296 KiB

tortoise

#include <bits/stdc++.h>

using i64 = long long;

#ifdef DEBUG
    #include "debug.h"
#else
    #define debug(...) void(23)
#endif

constexpr int inf = int(1E9);

template<typename T>
bool chmax(T& a, T b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}

int main() {
    std::ios_base::sync_with_stdio(false);
    std::cin.tie(nullptr);

    int N;
    std::cin >> N;

    std::vector<int> A(N);
    for (int i = 0; i < N; ++i) {
        std::cin >> A[i];
    }

    std::vector<int> minl(N, inf), minr(N, inf);
    for (int i = 0; i < N; ++i) {
        if (A[i] == -1) {
            minl[i] = 0;
            minr[i] = 0;
        }
    }
    for (int i = 1; i < N; ++i) {
        minl[i] = std::min(minl[i], minl[i - 1] + 1);
    }
    for (int i = N - 2; i >= 0; --i) {
        minr[i] = std::min(minr[i], minr[i + 1] + 1);
    }

    std::vector<std::vector<int>> f(N, std::vector<int>(3 * N + 1, -inf));
    f[0][0] = 0;

    for (int i = 0; i < N; ++i) {
        if (A[i] <= 0) {
            continue;
        }

        std::vector<std::vector<int>> g = f;
        for (int j = 0; j < N; ++j) {
            int d = std::abs(i - j);
            for (int k = 0; k <= 3 * N; ++k) {
                if (f[j][k] < 0) {
                    continue;
                }

                debug(j, k, f[j][k]);
                for (int a = 1; a <= A[i]; ++a) {
                    if (minl[i] != inf) {
                        int go = i - minl[i];
                        int need = d + (2 * a - 2) * std::min(minl[i], minr[i]);
                        if (k + need <= 2 * i) {
                            int tim = need + minl[i];
                            debug(go, k + tim, f[j][k] + a);
                            chmax(g[go][k + tim], f[j][k] + a);
                        }
                    }
                    if (minr[i] != inf) {
                        int go = i + minr[i];
                        int need = d + (2 * a - 2) * std::min(minl[i], minr[i]);
                        if (k + need <= 2 * i) {
                            int tim = need + minr[i];
                            debug(go, k + tim, f[j][k] + a);
                            chmax(g[go][k + tim], f[j][k] + a);
                        }
                    }
                }
            }
        }
        
        f = std::move(g);
        debug();
    }

    int ans = 0;
    for (int i = 0; i < N; ++i) {
        for (int j = 0; j <= 3 * N; ++j) {
           chmax(ans, f[i][j]);
        }
    }

    i64 sum = 0;
    for (int i = 0; i < N; ++i) {
        if (A[i] >= 0) {
            sum += A[i];
        }
    }

    std::cout << sum - ans << '\n';

    return 0;
}

• Subtask 1: 8 / 8
• Subtask 2: 10 / 10
• Subtask 3: 30 / 30
• Subtask 4: 0 / 25
• Subtask 5: 0 / 27