Submission #1057180

#	Time	Username	Problem	Language	Result	Execution time	Memory
1057180		SalihSahin	Robot (JOI21_ho_t4)	C++14	34 / 100	3091 ms	1612452 KiB

Main

#include<bits/stdc++.h>
#define pb push_back
#define ll long long
using namespace std;
 
const int mod = 1e9 + 7;
const int N = 1e5 + 5;
const ll inf = 1e17;
 
int main(){
    ios_base::sync_with_stdio(false), cin.tie(0), cout.tie(0);
    int n, m;
    cin>>n>>m;
    vector<array<int, 3> > adj[N];
    vector<ll> price[N];
 
    for(int i = 0; i < m; i++){
        int u, v, c, p;
        cin>>u>>v>>c>>p;
        array<int, 3> a1 = {v, c, p};
        array<int, 3> a2 = {u, c, p};
        adj[u].pb(a1);
        adj[v].pb(a2);
    }
 
    vector<ll> sum(N*2), cnt(N*2);
    vector<int> seen;
 
    for(int i = 1; i <= n; i++){
        price[i].resize(adj[i].size());
 
        for(auto itr: adj[i]){
            seen.pb(itr[1]);
            sum[itr[1]] += itr[2];
            cnt[itr[1]]++;
        }
        int ind = 0;
        for(auto itr: adj[i]){
            if(cnt[itr[1]] == 1) price[i][ind] = 0;
            else price[i][ind] = sum[itr[1]] - itr[2];
            ind++;
        }
 
        for(auto itr: seen){
            sum[itr] = 0;
            cnt[itr] = 0;
        }
        seen.clear();
    }
 
    map<int, int> vis[N];
    priority_queue<pair<ll, array<int, 4> > > pq;
    pq.push({0, {1, 0, 0, 0}});
    ll ans = inf;
 
    while(!pq.empty()){
        ll cost = -pq.top().first;
        int node = pq.top().second[0];
        int pre = pq.top().second[1];
        int prec = pq.top().second[2];
        int prep = pq.top().second[3];
        pq.pop();
 
        if(vis[node][pre]) continue;
        vis[node][pre] = 1;
        if(node == n){
            ans = cost;
            break;
        }
 
        if(pre == 0){ // nothing changed
            int ind = 0;
            for(auto itr: adj[node]){
                if(price[node][ind] > 0 && !vis[itr[0]][node]) pq.push({-(cost + itr[2]), {itr[0], node, itr[1], itr[2]}});
                if(itr[2] > price[node][ind] && !vis[itr[0]][0]) pq.push({-(cost + price[node][ind]), {itr[0], 0, 0, 0}});
                ind++;
            }
        }
        else{ // pre node changed, (- p[pre] in the case you dont change edge[node][nxt])
            int ind = 0;
            for(auto itr: adj[node]){
                if(price[node][ind] > 0 && !vis[itr[0]][node]) pq.push({-(cost + itr[2]), {itr[0], node, itr[1], itr[2]}});
                if(itr[2] > price[node][ind] - (itr[1] == prec ? prep : 0) && !vis[itr[0]][0]) pq.push({-(cost + price[node][ind] - (itr[1] == prec ? prep : 0)), {itr[0], 0, 0, 0}});
                ind++;
            }
        }
    }
 
    if(ans == inf) cout<<-1<<endl;
    else cout<<ans<<endl;
    return 0;
}
 
/*
4 6
1 4 4 4
3 4 1 3
1 3 4 4
2 4 3 1
2 3 3 2
1 2 4 2
 
5 7
2 3 7 1
1 4 5 1
4 5 3 1
3 4 7 1
2 4 3 1
3 5 6 1
1 2 5 1
*/

• Subtask 1: 34 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42