Submission #937255

#	Time	Username	Problem	Language	Result	Execution time	Memory
937255		Marco_Escandon	Commuter Pass (JOI18_commuter_pass)	C++11	100 / 100	400 ms	36076 KiB

commuter_pass

#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
#define x first
#define y second
vector<vector<ll>> v(5,vector<ll>(100001,1e16));
vector<vector<pair<ll,ll>>>G1(100001);
vector<vector<ll>>G2(100001);
void dijkstra(ll pl, ll node)
{
    priority_queue<pair<ll,ll>> q;
    q.push({0,node});
    while(!q.empty())
    {
        pair<ll,ll> a=q.top();q.pop();
        if(v[pl][a.y]==1e16)
        {
            v[pl][a.y]=-a.x;
            for(auto i:G1[a.y])
                if(v[pl][i.x]==1e16)
                    q.push({a.x-i.y,i.x});
        }
    }
}
vector<pair<ll,pair<ll,ll>>> dp(100001,{-1,{0,0}});
pair<ll,pair<ll,ll>> dfs(ll node, ll padre)
{
    if(dp[node].first!=-1)
        return dp[node];
    pair<ll,pair<ll,ll>> sol={v[2][node]+v[3][node],{v[2][node],v[3][node]}};
    for(auto i:G2[node])
    {
        if(i!=padre)
        {
            pair<ll,pair<ll,ll>> temp=dfs(i,node);
            sol.x=min(sol.x,temp.x);
            sol.x=min(sol.x,v[2][node]+temp.y.y);
            sol.x=min(sol.x,v[3][node]+temp.y.x);
            sol.y.x=min(sol.y.x,temp.y.x);
            sol.y.y=min(sol.y.y,temp.y.y);
        }
    }
    return dp[node]=sol;
}
int main()
{
    ll n,m;
    cin>>n>>m;
    ll s,t,u,w;
    cin>>s>>t>>u>>w;
    for(int i=0; i<m; i++)
    {
        ll a,b,c;
        cin>>a>>b>>c;
        G1[a].push_back({b,c});
        G1[b].push_back({a,c});
    }
    dijkstra(0,s);
    dijkstra(1,t);
    dijkstra(2,u);
    dijkstra(3,w);
    for(int i=1; i<=n; i++)
        for(auto j:G1[i])
            if(v[0][i]+v[1][j.x]+j.y==v[0][t])
                G2[i].push_back(j.x);
    cout<<min(dfs(s,0).x,v[2][w]);
}

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