Submission #681822

#	Time	Username	Problem	Language	Result	Execution time	Memory
681822		elkernos	Let's Win the Election (JOI22_ho_t3)	C++17	100 / 100	399 ms	2584 KiB

Main

// while (clock()<=69*CLOCKS_PER_SEC)
// #pragma comment(linker, "/stack:200000000")
// #pragma GCC optimize("O3")
// #pragma GCC target ("avx2")
// #pragma GCC optimize("Ofast")
// #pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
// #pragma GCC optimize("unroll-loops")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace __gnu_pbds;
using namespace std;

template <typename T>
using ordered_set =
    tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

#define sim template <class c
#define ris return *this
#define dor > debug &operator<<
#define eni(x)                                                                    \
    sim > typename enable_if<sizeof dud<c>(0) x 1, debug &>::type operator<<(c i) \
    {
sim > struct rge {
    c b, e;
};
sim > rge<c> range(c i, c j) { return rge<c>{i, j}; }
sim > auto dud(c *x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef XOX
    ~debug()
    {
        cerr << endl;
    }
    eni(!=) cerr << boolalpha << i;
    ris;
} eni(==) ris << range(begin(i), end(i));
}
sim, class b dor(pair<b, c> d)
{
    ris << "" << d.first << " --> " << d.second << "";
}
sim dor(rge<c> d)
{
    *this << "[";
    for (auto it = d.b; it != d.e; ++it)
        *this << ", " + 2 * (it == d.b) << *it;
    ris << "]";
}
#else
    sim dor(const c &)
    {
        ris;
    }
#endif
}
;
#define imie(...) " [" << #__VA_ARGS__ ": " << (__VA_ARGS__) << "] "

#ifdef XOX
#warning Times may differ!!!
#endif

#define endl '\n'
#define pb emplace_back
#define vt vector
#define rep(i, a, b) for (int i = a; i < (b); ++i)
#define all(x) begin(x), end(x)
#define sz(x) (int)(x).size()
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;

const int nax = 1000 * 1007, mod = 1e9 + 7;

int main()
{
    cin.tie(0)->sync_with_stdio(0);
    int n, k;
    cin >> n >> k;
    vt<pii> wek(n);
    for (auto &[a, b] : wek) {
        cin >> a >> b;
        if (b == -1) b = mod;
    }
    sort(all(wek), [](const pii &a, const pii &b) {
        return a.second < b.second;
    });
    typedef double T;
    auto solve_for = [&](int m) {
        vt<vt<T>> dp(n + 1, vt<T>(k - m + 1, mod));
        dp[0][0] = 0.;
        for (int i = 0; i < n; i++) {
            for (int j = 0; j <= k - m; j++) {
                int bylo = i - j;
                if (j < k - m) dp[i + 1][j + 1] = min(dp[i + 1][j + 1], dp[i][j] + (T)wek[i].first / (m + 1));
                dp[i + 1][j] = min(dp[i + 1][j], dp[i][j] + (bylo >= m ? 0. : (T)wek[i].second / (bylo + 1)));
            }
        }
        return dp[n][k - m];
    };
    int a = 0, b = k;
    while (b - a >= 3) {
        int p_1 = a + (b - a) / 3;
        int p_2 = b - (b - a) / 3;
        assert(p_1 != p_2);
        if (solve_for(p_1) <= solve_for(p_2)) b = p_2;
        else a = p_1;
    }
    T ans = mod;
    for (int i = 0; i <= k; i++) {
        debug() << imie(i) imie(solve_for(i));
    }
    debug() << imie(a) imie(b);
    for (int i = a; i <= b; i++) {
        ans = min(ans, solve_for(i));
    }
    cout << fixed << setprecision(15) << ans << endl;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 11 / 11
• Subtask 4: 12 / 12
• Subtask 5: 33 / 33
• Subtask 6: 11 / 11
• Subtask 7: 23 / 23