Submission #897490

# Submission time Handle Problem Language Result Execution time Memory
897490 2024-01-03T08:19:16 Z Der_Vlapos Seesaw (JOI22_seesaw) C++17
100 / 100
116 ms 23744 KB
// #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 MAXN = (1e5) + 5;
const int MOD7 = (1e9) + 7;
const int MOD9 = (1e9) + 9;
const uint MODFFT = 998244353;

#define int ll

struct test
{
    vector<int> pref;
    long double P;
    void solve(int testcase)
    {
        boost();

        int n;
        cin >> n;
        P = 0;
        pref.resize(n + 1);

        vector<int> a(n);
        cin >> a;
        for (int i = 1; i <= n; ++i)
            pref[i] = pref[i - 1] + a[i - 1];

        P = (long double)pref[n] / n;

        vector<pair<long double, int>> vals;
        vals.pb({P, n});

        for (int len = n - 1; len > 0; --len)
        {
            // [L ... L + len) <= P
            // [R ... R + len) > P
            int L = 0;
            int R = n - len;
            while (R - L > 1)
            {
                int M = (L + R) >> 1;
                if ((long double)(pref[M + len] - pref[M]) / len <= P)
                    L = M;
                else
                    R = M;
            }
            vals.pb({(long double)(pref[L + len] - pref[L]) / len, len});
            vals.pb({(long double)(pref[R + len] - pref[R]) / len, len});
        }
        sort(all(vals));
        vector<int> was(n + 1);
        int r = 0;
        int cnt = 0;
        long double res = 1e9 * 1e5;
        for (int l = 0; l < vals.size(); ++l)
        {
            while (cnt != n and r < vals.size())
            {
                cnt += (int)!(was[vals[r].s]);
                was[vals[r].s]++;
                r++;
            }
            if (cnt == n)
                res = min(res, vals[r - 1].f - vals[l].f);
            was[vals[l].s]--;
            cnt -= (int)!(was[vals[l].s]);
        }

        cout << fixed << setprecision(10);
        cout << res << "\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

seesaw.cpp: In member function 'void test::solve(long long int)':
seesaw.cpp:140:27: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long double, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  140 |         for (int l = 0; l < vals.size(); ++l)
      |                         ~~^~~~~~~~~~~~~
seesaw.cpp:142:35: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long double, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
  142 |             while (cnt != n and r < vals.size())
      |                                 ~~^~~~~~~~~~~~~
seesaw.cpp: At global scope:
seesaw.cpp:159:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  159 | main()
      | ^~~~
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 456 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 456 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 764 KB Output is correct
9 Correct 1 ms 600 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 2 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 0 ms 344 KB Output is correct
2 Correct 1 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 1 ms 456 KB Output is correct
7 Correct 1 ms 344 KB Output is correct
8 Correct 1 ms 764 KB Output is correct
9 Correct 1 ms 600 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 2 ms 604 KB Output is correct
12 Correct 116 ms 22488 KB Output is correct
13 Correct 112 ms 23744 KB Output is correct
14 Correct 114 ms 22124 KB Output is correct
15 Correct 111 ms 22944 KB Output is correct
16 Correct 113 ms 23216 KB Output is correct