Submission #922773

#	Time	Username	Problem	Language	Result	Execution time	Memory
922773		shenfe1	Collecting Stamps 3 (JOI20_ho_t3)	C++17	0 / 100	195 ms	520528 KiB

ho_t3

#pragma GCC target("avx2")
#pragma GCC optimize("O3")
#include <x86intrin.h>

#include <bits/stdc++.h>
#include <chrono>
#include <random>

// @author: Vlapos

namespace operators
{
    template <typename T1, typename T2>
    std::istream &operator>>(std::istream &in, std::pair<T1, T2> &x)
    {
        in >> x.first >> x.second;
        return in;
    }

    template <typename T1, typename T2>
    std::ostream &operator<<(std::ostream &out, std::pair<T1, T2> x)
    {
        out << x.first << " " << x.second;
        return out;
    }

    template <typename T1>
    std::istream &operator>>(std::istream &in, std::vector<T1> &x)
    {
        for (auto &i : x)
            in >> i;
        return in;
    }

    template <typename T1>
    std::ostream &operator<<(std::ostream &out, std::vector<T1> &x)
    {
        for (auto &i : x)
            out << i << " ";
        return out;
    }

    template <typename T1>
    std::ostream &operator<<(std::ostream &out, std::set<T1> &x)
    {
        for (auto &i : x)
            out << i << " ";
        return out;
    }
}

// name spaces
using namespace std;
using namespace operators;
// end of name spaces

// defines
#define ll long long
#define ull unsigned long long
#define pb push_back
#define mp make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define f first
#define s second
#define uint unsigned int
#define all(vc) vc.begin(), vc.end()
// end of defines

// usefull stuff

void boost()
{
    ios_base ::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
}

inline int getbit(int &x, int &bt) { return (x >> bt) & 1; }

const int dx4[4] = {-1, 0, 0, 1};
const int dy4[4] = {0, -1, 1, 0};
const int dx8[8] = {-1, -1, -1, 0, 0, 1, 1, 1};
const int dy8[8] = {-1, -0, 1, -1, 1, -1, 0, 1};

const ll INF = (1e18) + 500;
const int BIG = (1e9) * 2 + 100;
const int MOD7 = (1e9) + 7;
const int MOD9 = (1e9) + 9;
const uint MODFFT = 998244353;

// #define int ll

const int maxN = 405;
int dp[maxN][maxN][maxN][2];

struct test
{
    void solve(int testcase)
    {
        boost();

        int n, L;
        cin >> n >> L;

        vector<int> x(n), t(n);
        cin >> x >> t;
        x.pb(L);
        t.pb(-1);
        for (int i = 0; i < n; ++i)
        {
            x.pb(L + x[i]);
            t.pb(t[i]);
        }

        for (int i = 0; i < maxN; ++i)
            for (int j = 0; j < maxN; ++j)
                for (int k = 0; k < maxN; ++k)
                    for (int fl = 0; fl < 2; ++fl)
                        dp[i][j][k][fl] = BIG;

        dp[n][n][0][0] = dp[n][n][0][1] = 0;

        int ans = 0;
        int bestRes = 0;
        int N = x.size();
        int r = 0, cord = 0, tocnt = 0;
        for (int len = 0; len + 1 < N; ++len)
            for (int l = 0; l < N and l + len < N; ++l)
            {
                r = l + len;
                for (int cnt = 0; cnt < n; ++cnt)
                    for (int fl = 0; fl < 2; ++fl)
                        if (dp[l][r][cnt][fl] != BIG)
                        {
                            cord = fl ? x[r] : x[l];
                            if (l)
                            {
                                tocnt = cnt + (int)(t[l - 1] >= abs(cord - x[l - 1]) + dp[l][r][cnt][fl]);
                                ans = max(ans, tocnt);
                                dp[l - 1][r][tocnt][0] = min(dp[l - 1][r][tocnt][0], abs(cord - x[l - 1]) + dp[l][r][cnt][fl]);
                            }
                            if (r + 1 < N)
                            {
                                tocnt = cnt + (int)(t[r + 1] >= abs(cord - x[r + 1]) + dp[l][r][cnt][fl]);
                                ans = max(ans, tocnt);
                                dp[l][r + 1][tocnt][1] = min(dp[l][r + 1][tocnt][1], abs(cord - x[r + 1]) + dp[l][r][cnt][fl]);
                            }
                        }
            }

        cout << ans << "\n";
    }
};

main()
{
    boost();
    int q = 1;
    // cin >> q;
    for (int i = 0; i < q; i++)
    {
        test t;
        t.solve(i);
    }
    return 0;
}
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//
//                                                                                    //
//                               Coded by Der_Vlἀpos                                  //
//                                                                                    //
//[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]//

Compilation message (stderr)

ho_t3.cpp: In member function 'void test::solve(int)':
ho_t3.cpp:125:13: warning: unused variable 'bestRes' [-Wunused-variable]
  125 |         int bestRes = 0;
      |             ^~~~~~~
ho_t3.cpp: At global scope:
ho_t3.cpp:156:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  156 | main()
      | ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 75