Submission #1274319

#	Time	Username	Problem	Language	Result	Execution time	Memory
1274319		quan606303	Robot (JOI21_ho_t4)	C++20	100 / 100	758 ms	139640 KiB

Main

/*
 * @Author: RMQuan 
 * @Date: 2025-09-29 22:50:45 
 * @Last Modified by: RMQuan
 * @Last Modified time: 2025-09-30 03:35:55
 */
/*idea :

*/

#include <bits/stdc++.h>
bool M1;
#define int long long
#define ll long long
#define fi first
#define se second
#define memfull(a,b) memset(a,b,sizeof(a));
#define endl '\n'
#define file(a) freopen(a".inp","r",stdin); freopen(a".out","w",stdout);
using namespace std;
const int maxn=2e5+7;
const ll INF=1e18;

struct Edge {
    int to,c;
    ll w;
};

map<int, vector<Edge>> graph[maxn];
unordered_map<int,ll> dis[maxn];
unordered_map<int,bool> vst[maxn];
map<int,ll> psum[maxn];

struct node {
    int u,prev_col;
    ll dist;
};
struct cmp {
    bool operator()(const node &a,const node &b) const {
        return a.dist>b.dist;
    }
};

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n,m;
    cin>>n>>m;
    for(int i=1;i<=m;i++) {
        int u,v,c;
        ll w;
        cin>>u>>v>>c>>w;
        graph[u][c].push_back({v,c,w});
        graph[v][c].push_back({u,c,w});
        psum[u][c]+=w;
        psum[v][c]+=w;
    }

    priority_queue<node,vector<node>,cmp> pq;
    dis[1][-1]=0;
    pq.push({1,-1,0});

    while(!pq.empty()) {
        auto cur=pq.top(); pq.pop();
        int u=cur.u, col=cur.prev_col;
        ll du=cur.dist;
        if(vst[u][col]) continue;
        vst[u][col]=true;

        if(col==-1) {
            for(auto &p:graph[u]) {
                int c=p.fi;
                for(auto &e:p.se) {
                    if(dis[e.to].find(-1)==dis[e.to].end()||dis[e.to][-1]>du+psum[u][c]-e.w) {
                        dis[e.to][-1]=du+psum[u][c]-e.w;
                        pq.push({e.to,-1,dis[e.to][-1]});
                    }
                    if(dis[e.to].find(-1)==dis[e.to].end()||dis[e.to][-1]>du+e.w) {
                        dis[e.to][-1]=du+e.w;
                        pq.push({e.to,-1,dis[e.to][-1]});
                    }
                    if(dis[e.to].find(c)==dis[e.to].end()||dis[e.to][c]>du) {
                        dis[e.to][c]=du;
                        pq.push({e.to,c,du});
                    }
                }
            }
        } else {
            for(auto &e:graph[u][col]) {
                if(dis[e.to].find(-1)==dis[e.to].end()||dis[e.to][-1]>du+psum[u][col]-e.w) {
                    dis[e.to][-1]=du+psum[u][col]-e.w;
                    pq.push({e.to,-1,dis[e.to][-1]});
                }
            }
        }
    }

    cout<<(dis[n].count(-1)?dis[n][-1]:-1);

    bool M2;
    cerr<<"-------------------------------------------------\n";
    cerr<<"Time : "<<clock()<<" ms\n";
    cerr<<"Memory : "<<abs(&M2-&M1)/1024/1024<<" MB\n";
    cerr<<"-------------------------------------------------\n";
    return 0;
}

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