제출 #1170632

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1170632		anmattroi	봉쇄 시간 (IOI23_closing)	C++17	0 / 100	51 ms	17220 KiB

closing

#include "closing.h"
#include <bits/stdc++.h>
#define maxn 200005
#define fi first
#define se second
using namespace std;
using ii = pair<int, int>;

int n, x, y; int64_t k;

int64_t dp[2005][2005];
int64_t disX[2005], disY[2005];

int64_t cost_level_one[2005], cost_level_two[2005];

vector<ii> adj[2005];

void calcdisX() {

    function<void(int, int)> dfs = [&](int u, int dad) {
        for (auto [v, l] : adj[u])
        if (v != dad) {
            disX[v] = disX[u] + l;
            dfs(v, u);
        }
    };

    disX[x] = 0;
    dfs(x, -1);
}

void calcdisY() {

    function<void(int, int)> dfs = [&](int u, int dad) {
        for (auto [v, l] : adj[u])
        if (v != dad) {
            disY[v] = disY[u] + l;
            dfs(v, u);
        }
    };

    disY[y] = 0;
    dfs(y, -1);
}

int solve() {
    calcdisX(); calcdisY();

    for (int i = 0; i < n; i++)
        cost_level_two[i] = max(disX[i], disY[i]) - (cost_level_one[i] = min(disX[i], disY[i]));

    for (int i = 1; i <= n; i++) dp[n][i] = LLONG_MAX/100;

    for (int i = n-1; i >= 0; i--) {
        for (int j = 1; j <= n; j++) dp[i][j] = dp[i+1][j];
        for (int j = 0; j <= n; j++) {
            if (j+1 <= n) dp[i][j+1] = min(dp[i][j+1], dp[i+1][j] + cost_level_one[i]);
            if (j+2 <= n) dp[i][j+2] = min(dp[i][j+2], dp[i+1][j] + cost_level_one[i] + cost_level_two[i]);
        }
    }


    int ans = 0;
    for (int i = 0; i <= n; i++) if (dp[0][i] <= k) ans = i;
    return ans;
}

int max_score(int N, int X, int Y, long long K, vector<int> U, vector<int> V, vector<int> W) {
    n = N; x = X; y = Y; k = K;
    for (int i = 0; i < N-1; i++) {
        adj[U[i]].emplace_back(V[i], W[i]);
        adj[V[i]].emplace_back(U[i], W[i]);
    }
    int ans = solve();
    for (int i = 0; i < N; i++) adj[i].clear();
    for (int i = 0; i <= N; i++) for (int j = 0; j <= N; j++) dp[i][j] = 0;
    return ans;
}

• Subtask 0: 0 / 0
• Subtask 1: 0 / 8
• Subtask 2: 0 / 9
• Subtask 3: 0 / 12
• Subtask 4: 0 / 14
• Subtask 5: 0 / 9
• Subtask 6: 0 / 11
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 17