Submission #964380

#	Time	Username	Problem	Language	Result	Execution time	Memory
964380		emad234	Cyberland (APIO23_cyberland)	C++17	8 / 100	1598 ms	2097152 KiB

cyberland

#include <bits/stdc++.h>
#define all(v) ((v).begin(), (v).end())
#define F first
#define S second
typedef long long ll;
#define pii pair<ll, double>
using namespace std;
const ll mod = 1e9 + 7;
const ll mxN = 4e6 + 5;
struct path
{
    ll i, k;
    double val;
};
bool operator<(path a, path b)
{
    return a.val < b.val;
}
bool operator>(path a, path b)
{
    return a.val > b.val;
}
double solve(int N, int M, int K, int H, vector<int> x, vector<int> y, vector<int> c, vector<int> arr)
{
    vector<vector<double>>dp;  
    vector<int>vis;
    vector<vector<pii>> v;
    dp.resize(N + 3);
    vis.resize(N + 3);
    v.resize(N + 3);
    for (int i = 0; i < M; i++)
    {
        v[x[i]].push_back({y[i], (double)c[i]});
        v[y[i]].push_back({x[i], (double)c[i]});
    }
    for(int i = 0;i < N;i++){
        dp[i].resize(K + 3);
        for(int j = 0;j <= K;j++){
            dp[i][j] = 1e18;
        }
    }
    priority_queue<path,vector<path>,greater<path>>q;
    queue<int>bfs;
    bfs.push(0);
    q.push({0,0,0});
    dp[0][0] = 0;
    while(bfs.size()){
        auto u = bfs.front();
        vis[u] = 1;
        bfs.pop();
        if(arr[u] == 0) {
            q.push({u,0,0});
            dp[u][0] = 0;
        }
        for(auto x : v[u]){
            if(!vis[x.F]){
                vis[x.F] = 1;
                bfs.push(x.F);
            }
        }
    }
    while(q.size()){
        auto u = q.top();
        q.pop();
        if(u.val < dp[u.i][u.k]) continue;
        for(auto x : v[u.i]){
            if(dp[x.F][u.k] > dp[u.i][u.k] + x.S){
                dp[x.F][u.k] = dp[u.i][u.k] + x.S;
                q.push({x.F,u.k,dp[x.F][u.k]});
            }
            if(u.k != K && arr[u.i] == 2 && dp[x.F][u.k + 1] > dp[u.i][u.k] / 2 + x.S){
                dp[x.F][u.k + 1] = dp[u.i][u.k] / 2 + x.S;
                q.push({x.F,u.k + 1,dp[x.F][u.k + 1]});
            }
        }
    }
    double ans = 1e18;
    for(int i = 0;i <= K;i++){
        ans = min(ans,dp[H][i]);
    }
    return ans;
}

// int main()
// {
//     int T;
//     assert(1 == scanf("%d", &T));
//     while (T--)
//     {
//         int N, M, K, H;
//         assert(4 == scanf("%d %d %d\n%d", &N, &M, &K, &H));
//         vector<int> x(M);
//         vector<int> y(M);
//         vector<int> c(M);
//         vector<int> arr(N);
//         for (int i = 0; i < N; i++)
//             assert(1 == scanf("%d", &arr[i]));
//         for (int i = 0; i < M; i++)
//             assert(3 == scanf("%d %d %d", &x[i], &y[i], &c[i]));
//         printf("%.12lf\n", solve(N, M, K, H, x, y, c, arr));
//     }
// }

• Subtask 1: 0 / 5
• Subtask 2: 8 / 8
• Subtask 3: 0 / 13
• Subtask 4: 0 / 19
• Subtask 5: 0 / 7
• Subtask 6: 0 / 16
• Subtask 7: 0 / 29
• Subtask 8: 0 / 3