제출 #1067403

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1067403		Whisper	Let's Win the Election (JOI22_ho_t3)	C++17	10 / 100	631 ms	6480 KiB

Main

#include <bits/stdc++.h>

using namespace std;
using ll = long long;

#define int long long
#define FOR(i, a, b) for (int i = (a); i <= (b); i++)
#define FORD(i, a, b) for (int i = (b); i >= (a); i --)
#define REP(i, a) for (int i = 0; i < (a); ++i)
#define REPD(i, a) for (int i = (a) - 1; i >= 0; --i)

#define MASK(i) (1LL << (i))
#define BIT(x, i) (((x) >> (i)) & 1)


constexpr ll LINF = (1ll << 60);
constexpr int INF = (1ll << 30);
constexpr int Mod = 1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

/*
    Phu Trong from Nguyen Tat Thanh High School for gifted student
*/

template <class X, class Y>
    bool minimize(X &x, const Y &y){
        X eps = 1e-2;
        if (x > y + eps) {x = y; return 1;}
        return 0;
    }

template <class X, class Y>
    bool maximize(X &x, const Y &y){
        X eps = 1e-2;
        if (x + eps < y) {x = y; return 1;}
        return 0;
    }
#define MAX                 505
int N, K;
int A[MAX], B[MAX];

double dp[2][MAX][MAX];

int cost[MAX][MAX];
void process(void){
    cin >> N >> K;
    for (int i = 1; i <= N; ++i){
        cin >> A[i] >> B[i];
        if(B[i] == -1) B[i] = 1e18;
    }
    vector<int> order(N);
    iota(order.begin(), order.end(), 1);

    sort(order.begin(), order.end(), [&](int &i, int &j){
        return B[i] < B[j];
    });

    vector<int> vals;
    FOR(i, 0, N - 1) FOR(j, 0, K) cost[i][j] = 1e18;
    for (int i = N - 1; i >= 0; --i){
        vals.push_back(A[order[i]]);
        sort(vals.begin(), vals.end());
        int sm = 0;
        for (int j = 0; j < (int)vals.size(); ++j){
            sm += vals[j];
            cost[i][j + 1] = sm;
        }
    }
    FOR(j, 0, K) FOR(k, 0, K) dp[0][j][k] = dp[1][j][k] = 1e15;
    double ans = cost[0][K];
    dp[0][0][0] = 0;
    for (int i = 0; i < N; ++i){
        for (int j = 0; j <= K; ++j){
            for (int k = 0; k <= K; ++k){
                dp[1][j][k] = 1e15;
            }
        }

        for (int j = 0; j <= K; ++j){
            for (int k = 0; k <= K; ++k){
                minimize(dp[1][j][k], dp[0][j][k]);
                if(j > 0)
                    minimize(dp[1][j][k], dp[0][j - 1][k] + (double)A[order[i]] / (double)(k + 1));
                if(j > 0 && k > 0)
                    minimize(dp[1][j][k], dp[0][j - 1][k - 1] + (double)B[order[i]] / (double)(k));

                int need = K - j;
                if(N - i - 1 >= need)
                    minimize(ans, dp[1][j][k] + (double)cost[i + 1][need] / (double)(k + 1));
            }
        }
        swap(dp[0], dp[1]);
    }
    cout << setprecision(10) << fixed << ans;
}
signed main(){
    #define name "Whisper"
    cin.tie(nullptr) -> sync_with_stdio(false);
    //freopen(name".inp", "r", stdin);
    //freopen(name".out", "w", stdout);
    process();
    return (0 ^ 0);
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 11
• Subtask 4: 0 / 12
• Subtask 5: 0 / 33
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23