Submission #879233

#	Time	Username	Problem	Language	Result	Execution time	Memory
879233		dimashhh	Cyberland (APIO23_cyberland)	C++17	0 / 100	32 ms	42076 KiB

cyberland

#include <bits/stdc++.h>
#include "cyberland.h"
#pragma GCC optimize("Ofast","O3","unroll-loops")
#pragma GCC target("avx2")
using namespace std;
typedef long long ll;
const int N = 1e5 + 1;
vector<pair<int, double>> g[N];
double d[N][70];
double solve(int n, int m, int k, int h, std::vector<int> x, std::vector<int> y, std::vector<int> c, std::vector<int> arr)
{   
    k = min(k,69);
    for (int i = 0; i < n; i++)
    {
        for(int j = 0;j <= k;j++){
            d[i][j] = 1e15;
        }
        g[i].clear();
    }
    
    for (int i = 0; i < m; i++)
    {
        g[x[i]].push_back({y[i], c[i]});
        g[y[i]].push_back({x[i], c[i]});
    }
    queue<int> q;
    vector<int> can(n,0);
    can[0] = 1;
    q.push(0);
    while(!q.empty()){
        int v = q.front();
        q.pop();
        for(auto [to,w]:g[v]){
            if(to == h || can[to]) continue;
            q.push(to);
            can[to] = 1;
        }
    }
    priority_queue<pair<double,pair<int,int>>> st;
    st.push({0,{0,0}});
    for (int j = 0; j < n; j++)
    {
        if ((!arr[j] && can[j]) || !j)
        {
            st.push({0,{0,j}});
            d[j][0] = 0;
        }
    }
    double res = 1e15;
    while(!st.empty()){
        auto [col,v] = (st.top()).second;
        st.pop();
      	double val = (st.top()).first;
      	
        if(v == h){
            res = min(res,d[v][col]);
            continue;
        }
	    if(d[v][col] != val) continue;
        for(auto [to,w]:g[v]){
            if(col + 1 <= k && arr[to] == 2 && d[to][col + 1] > (d[v][col] + w) / 2){
                d[to][col + 1] = (d[v][col] + w) / 2;
                st.push({-d[to][col + 1],{col + 1,to}});
            }
            if(d[to][col] > d[v][col] + w){
                d[to][col] = d[v][col] + w;
                st.push({-d[to][col],{col,to}});
            }
        }
    }
    if(res == 1e15) res = -1;
    return res;
}
// 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));
//     std::vector<int> x(M);
//     std::vector<int> y(M);
//     std::vector<int> c(M);
//     std::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: 0 / 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