Submission #94336

#	Time	Username	Problem	Language	Result	Execution time	Memory
94336		dalgerok	Cities (BOI16_cities)	C++14	100 / 100	2673 ms	44888 KiB

cities

#include<bits/stdc++.h>
using namespace std;


const int N = 1e5 + 5, M = (1 << 5) + 5;
const long long INF = 1e18;


bool used[N];
int n, k, m, val[N];
vector < pair < int, int > > g[N];
long long d[M][N];


int main(){
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n >> k >> m;
    for(int i = 0; i < (1 << k); i++){
        for(int j = 1; j <= n; j++){
            d[i][j] = INF;
        }
    }
    for(int i = 0; i < k; i++){
        int x;
        cin >> x;
        val[x] = (1 << i);
        d[val[x]][x] = 0;
    }
    for(int i = 1; i <= m; i++){
        int x, y, z;
        cin >> x >> y >> z;
        g[x].push_back(make_pair(y, z));
        g[y].push_back(make_pair(x, z));
    }
    for(int mask = 1; mask < (1 << k); mask++){
        priority_queue < pair < long long, int > > q;
        for(int i = 0; i < mask; i++){
            if((mask | i) != mask){
                continue;
            }
            for(int j = 1; j <= n; j++){
                d[mask][j] = min(d[mask][j], d[i][j] + d[(mask ^ i)][j]);
            }
        }
        for(int i = 1; i <= n; i++){
            used[i] = false;
            if(d[mask][i] != INF){
                q.push(make_pair(-d[mask][i], i));
            }
        }
        while(!q.empty()){
            long long val = -q.top().first;
            int v = q.top().second;
            q.pop();
            if(used[v]){
                continue;
            }
            used[v] = true;
            for(auto it : g[v]){
                int to = it.first;
                long long nxt = val + it.second;
                if(d[mask][to] > nxt){
                    d[mask][to] = nxt;
                    q.push(make_pair(-d[mask][to], to));
                }
            }
        }
    }
    long long ans = INF;
    for(int i = 1; i <= n; i++){
        ans = min(ans, d[(1 << k) - 1][i]);
    }
    cout << ans;
}

• Subtask 1: 22 / 22
• Subtask 2: 14 / 14
• Subtask 3: 15 / 15
• Subtask 4: 23 / 23
• Subtask 5: 26 / 26