Submission #972140

#	Time	Username	Problem	Language	Result	Execution time	Memory
972140		boyliguanhan	Robot (JOI21_ho_t4)	C++17	100 / 100	1424 ms	141160 KiB

Main

#include<bits/stdc++.h>
using namespace std;
#define int long long
#define PB push_back
#define djik(a,b,w) if(dis[a][b]>w)pq.push({dis[a][b]=w,a,b})
#define M 7<<14
vector<int> N[M],E[M],P[M],C[M],dis[M];
map<int,int>mp[M];
map<int,set<pair<int,int>>>mp2[M];
signed main(){
    cin.tie(0)->sync_with_stdio(0);
    int n,m;
    cin>>n>>m;
    for(int i=1;i<=n;i++)
        N[i].PB(0),E[i].PB(0),C[i].PB(0),P[i].PB(0),dis[i].PB(1e18);
    dis[1][0]=0;
    while(m--){
        int a,b,c,d;
        cin>>a>>b>>c>>d;
        mp[a][c]+=d;
        mp[b][c]+=d;
        dis[a].PB(1e18);
        dis[b].PB(1e18);
        E[a].PB(size(P[b]));
        E[b].PB(size(P[a]));
        P[a].PB(d),P[b].PB(d);
        N[a].PB(b),N[b].PB(a);
        mp2[b][c].insert({d,size(C[b])});
        mp2[a][c].insert({d,size(C[a])});
        C[a].PB(c),C[b].PB(c);
    }
    priority_queue<tuple<int,int,int>,vector<tuple<int,int,int>>,greater<>>pq;
    pq.push({0,1,0});
    while(pq.size()){
        auto[w,x,e]=pq.top();
        pq.pop();
        if(dis[x][e]<w)
            continue;
        djik(x,0,w);
        if(e){
            if(mp[x][C[x][e]]==P[x][e])
                continue;
            int y=(--mp2[x][C[x][e]].end())->second;
            if(y==e)
                y=prev(--mp2[x][C[x][e]].end())->second;
            djik(N[x][y],0,w+mp[x][C[x][e]]-P[x][e]-P[x][y]);
        } else {
            for(int i=1;i<P[x].size();i++) {
                djik(N[x][i],E[x][i],w+P[x][i]);
                djik(N[x][i],0,w+mp[x][C[x][i]]-P[x][i]);
            }
        }
    }
    cout<<(dis[n][0]<1e18?dis[n][0]:-1);
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:48:26: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |             for(int i=1;i<P[x].size();i++) {
      |                         ~^~~~~~~~~~~~

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