Submission #745772

#	Time	Username	Problem	Language	Result	Execution time	Memory
745772		vjudge1	Cities (BOI16_cities)	C++17	14 / 100	261 ms	18320 KiB

cities

#include <bits/stdc++.h>

// #define MULTI_TEST_CASE
// #define TEST_TEXT

using namespace std;

#define ll long long
#define MAX(a, b) (a) = max((a), (b))
#define MIN(a, b) (a) = min((a), (b))
#define all(a) (a).begin(), (a).end()
#define sortedpair(a, b) {min((a), (b)), max((a), (b))}

const ll MOD = 1e9+7;

struct edge {
    int to, w;
};


int n, k, m;
vector<vector<edge>> v;
vector<int> w;

vector<ll> dijkstra(int start){
    vector<ll> d1(n, 1e18);
    d1[start] = 0;
    priority_queue<pair<ll, int>> q;
    q.push({0, start});
    while(!q.empty()){
        ll d = -q.top().first;
        int c = q.top().second;
        q.pop();
        if(d > d1[c])continue;
        for(auto&i : v[c]){
            if(d + i.w < d1[i.to]){
                d1[i.to] = d + i.w;
                q.push({-d1[i.to], i.to});
            }
        }
    }
    return d1;
}

void solve(){
    cin>>n>>k>>m;
    w.assign(k, 0);
    for(int&i:w){cin>>i; i--;}
    v.assign(n, {});
    for(int i = 0; i < m; i++){
        int a, b, c; cin>>a>>b>>c; a--; b--;
        v[a].push_back({b, c});
        v[b].push_back({a, c});
    }

    vector<ll> d1 = dijkstra(w[0]);
    vector<ll> d2 = dijkstra(w[1]);
    vector<ll> d3;
    if(k == 2){
        d3.assign(n, 0);
    } else {
        d3 = dijkstra(w[2]);
    }
    ll ans = 1e18;
    for(int i = 0; i < n; i++){
        MIN(ans, d1[i] + d2[i] + d3[i]);
    }
    cout<<ans<<endl;
}

int main(){
    ios_base::sync_with_stdio(0); cin.tie(0);
    int _t = 1;
#ifdef MULTI_TEST_CASE
    cin >> _t;
#endif
    for(int _i = 0; _i < _t; _i++){
        #ifdef TEST_TEXT
        cout<<"Case #"<<_i+1<<": ";
        #endif
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 22
• Subtask 2: 14 / 14
• Subtask 3: 0 / 15
• Subtask 4: 0 / 23
• Subtask 5: 0 / 26