Submission #1197960

#	Time	Username	Problem	Language	Result	Execution time	Memory
1197960		guanex	Robot (JOI21_ho_t4)	C++20	34 / 100	3096 ms	64600 KiB

Main

#include<bits/stdc++.h>

using namespace std;

typedef long long ll;
#define endl '\n'

//data structures

typedef pair<ll, ll> ii;
typedef vector<ii> vii;
typedef vector<ll> vll;
typedef vector<ll> vi;
typedef vector<vector<ll>> vvi;
#define pb push_back
#define sz(a) ((int)a.size())
#define whole(v) v.begin(), v.end()
#define rwhole(v) v.rbegin(), v.rend()
#define pqueue priority_queue

//answers

const ll inf = ll(1e18);

// read arr vec matr etc

#define fill(x, y) memset(x, y, sizeof(x))

// Solution

struct cmp{
    bool operator()(vi &a, vi &b){
        return a[0] > b[0];
    }
};

void tc(){
    int n, m; cin >> n >> m;
    ll dp[m][2]; //edge idx, color matters y/n
    vector<vector<int>> ed(n);
    vector<vector<int>> edges;
    vector<unordered_map<int, ll>> x(n);
    for(int i = 0; i < m; ++i){
        dp[i][0] = inf; dp[i][1] = inf;
        int u, v, col, cost; cin >> u >> v >> col >> cost;
        u--;
        v--;
        edges.pb({u, v, col, cost});
        ed[u].pb(i);
        ed[v].pb(i);
        x[u][col] += cost;
        x[v][col] += cost;
    }
    pqueue<vi, vvi, cmp> pq;
    ll totcost = 0;
    bool othernode = 0;
    for(auto e:ed[0]){
        totcost = x[0][edges[e][2]];
        totcost -= edges[e][3];
        othernode = 1;
        if(edges[e][0] != 0){
            othernode = 0;
        }
        pq.push({edges[e][3], e, othernode, 0});
        pq.push({totcost, e, othernode, 1});
        dp[e][0] = edges[e][3];
        dp[e][1] = totcost;
    }

    ll cost = 0; 
    while(!pq.empty()){
        int idx = pq.top()[1];
        cost = pq.top()[0];
        int no = edges[idx][pq.top()[2]];
        bool fat = pq.top()[3];
        pq.pop();
        if(dp[idx][fat] != cost)continue;
        for(auto e:ed[no]){
            if(e == idx)continue;
            bool me = 0;
            if(edges[e][0] == no){
                me = 1;
            }
            totcost = x[no][edges[e][2]];
            totcost -= edges[e][3];
            if(fat == 0 && edges[idx][2] == edges[e][2]){
                totcost -= edges[idx][3];
            }
            if(dp[e][0] > cost + edges[e][3]){
                dp[e][0] = cost + edges[e][3];
                pq.push({cost + edges[e][3], e, me, 0});
            }
            if(dp[e][1] > cost + totcost){
                dp[e][1] = cost + totcost;
                pq.push({cost + totcost, e, me, 1});
            }
        }
    }
    ll ans = inf;
    for(auto e:ed[n-1]){
        ans = min(ans, min(dp[e][0], dp[e][1]));
    }
    if(ans == inf) cout << -1 << endl;
    else cout << ans << endl;
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0); cout.tie(0);
    int t = 1;
    while(t--){
        tc();
    }
}

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