Submission #1167622

#	Time	Username	Problem	Language	Result	Execution time	Memory
1167622		liza	Commuter Pass (JOI18_commuter_pass)	C++20	0 / 100	2095 ms	15032 KiB

commuter_pass

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target ("avx2,bmi,bmi2,popcnt,lzcnt")
using namespace std;

const int N = 100005;
vector<pair<int, long long>> graph[N];

long long dv[N], dt[N], ds[N];
int main()
{
    ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
    int n, m, s, t, u, v; cin >> n >> m >> s >> t >> u >> v;

    for(int i = 0; i < m; i++)
    {
        int a, b;
        long long c;
        cin >> a >> b >> c;
        graph[a].push_back({b, c});
        graph[b].push_back({a, c});
    }
    priority_queue <pair<long long, int>> pq;
    for(int i = 0; i <= n; i++)ds[i]= 1e18;
    ds[s]=0;
    pq.push({0, s});
    while(pq.size())
    {
        pair<long long,int> x = pq.top();
        pq.pop();
        for(auto i: graph[x.second])
        {
            if(ds[i.first] > x.first+i.second)
            {
                pq.push({x.first+i.second, i.first});
                ds[i.first]=x.first+i.second;
            }
        }
    }

    for(int i = 0; i <= n; i++)dt[i]= 1e18;
    dt[t]=0;
    pq.push({0, t});
    while(pq.size())
    {
        pair<long long,int> x = pq.top();
        pq.pop();
        for(auto i: graph[x.second])
        {
            if(dt[i.first] > x.first+i.second)
            {
                pq.push({x.first+i.second, i.first});
                dt[i.first]=x.first+i.second;
            }
        }
    }


    for(int i = 0; i <= n; i++)dv[i]= 1e18;
    dv[v]=0;
    pq.push({0, v});
    while(pq.size())
    {
        pair<long long,int> x = pq.top();
        pq.pop();
        for(auto i: graph[x.second])
        {
            if(dv[i.first] > x.first+i.second)
            {
                pq.push({x.first+i.second, i.first});
                dv[i.first]=x.first+i.second;
            }
        }
    }
    /*
    int du[100005]={0};
    du[u]=0;
    priv = u;
    pq.push({0, u});
    while(pq.size())
    {
        pair<int,int> x = pq.top();
        pq.pop();
        for(auto i: graph[x.second])
        {
            if(i.first==priv)continue;
            if(du[i.first]==0 || du[i.first] > x.first+i.second)
            {
                pq.push({x.first+i.second, i.first});
                du[i.first]=x.first+i.second;
            }
        }
        priv=x.second;
    }
    */
    long long rezv= 1e18;
    for(int i = 1; i <= n; i++)
    {
        if(dv[i] < rezv)
        {
            if(dt[i]+ds[i]==ds[t])
            {
                rezv=dv[i];
            }
        }
    }
    cout << rezv << "\n";
    return 0;
}

• Subtask 1: 0 / 16
• Subtask 2: 0 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45