Submission #679351

#	Time	Username	Problem	Language	Result	Execution time	Memory
679351		Hiennoob123	Commuter Pass (JOI18_commuter_pass)	C++14	15 / 100	2081 ms	27056 KiB

commuter_pass

#include<bits/stdc++.h>
#define ll long long
#define int long long
#define ld long double
#define cd complex<ld>
#define pll pair<ll,ll>
#define pii pair<int,int>
#define pld pair<ld,ld>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
using namespace std;
ll n, m;
vector<pll> T[100005];
ll save[4];
ll dis[4][100005];
bool chk[100005];
bool in[100005];
ll dp[100005];
ll sum[100005];
vector<ll> adj[100005];
ll ans = LLONG_MAX;
void dijsktra(ll type)
{
    for(int i = 1; i<= n; i++) dis[type][i] = LLONG_MAX;
    for(int i = 1; i<= n; i++) chk[i] = 0;
    priority_queue<pll,vector<pll>, greater<pll>> q;
    dis[type][save[type]] = 0;
    q.push(mp(0 , save[type]));
    while(!q.empty())
    {
        ll path = q.top().fi, x = q.top().se;
        q.pop();
        if(chk[x]||dis[type][x]!=path) continue;
        //cout << type << " " << path << " " << x << "-\n";
        chk[x] = 1;
        for(auto u: T[x])
        {
            ll cur = path+u.se;
            if(cur<dis[type][u.fi])
            {
                dis[type][u.fi] = cur;
                q.push(mp(dis[type][u.fi], u.fi));
            }
        }
    }
}
void dfs(ll v)
{
    for(auto x: adj[v])
    {
        dfs(x);
        dp[v] = min(dp[v], dp[x]);
    }
    ans = min(ans, dp[v]+sum[v]);
}
void solve()
{
    cin >> n >> m;
    cin >> save[2] >> save[3] >> save[0] >> save[1];
    for(int i = 0 ;i< m; i++)
    {
        ll a, b, c;
        cin >> a >> b >> c;
        T[a].push_back(mp(b,c));
        T[b].push_back(mp(a,c));
    }
    dijsktra(2); dijsktra(3);
    //cout << dis[2][save[3]] << "\n";
    for(int i = 1; i<= n; i++)
    {
        //cout << dis[2][i] << " " << dis[3][i] << " " << i << "\n";
        if(dis[2][save[3]]==dis[2][i]+dis[3][i])
        {
            //cout << i << "\n";
            in[i] = 1;
        }
    }

    for(int i = 1; i<= n; i++)
    {
        if(!in[i]) continue;
        //cout << i << "\n";
        for(auto x: T[i])
        {
            if(!in[x.fi]||dis[2][i]+x.se!=dis[2][x.fi]) continue;
            adj[i].push_back(x.fi);
            //cout << i << " "  << x.fi << "\n";
        }
    }
    dijsktra(0); dijsktra(1);
    for(int i = 1; i<= n; i++)
    {
        //cout << dis[1][i] << " " << dis[0][i] << " " << i << "\n";
        dp[i] = dis[1][i];
        sum[i] = dis[0][i];
    }
    dfs(save[2]);
    for(int i = 1 ; i<= n; i++)
    {
        //cout << dp[i] << " " << sum[i] << " " << i << "\n";
    }
    swap(save[0],save[1]);
    dijsktra(0); dijsktra(1);
    for(int i = 1; i<= n; i++)
    {
        dp[i] = dis[1][i];
        sum[i] = dis[0][i];
    }
    dfs(save[2]);
    cout << min(ans, dis[0][save[1]]);
}
signed main()
{
    //freopen("IN.txt","r",stdin);
    //freopen("OUT.txt","w",stdout);
    ios_base::sync_with_stdio(NULL) ; cin.tie(nullptr) ; cout.tie(nullptr);
    ll t = 1;
    //cin >> t;
    while(t--)
    {
        solve();
        cout << "\n";
    }
}

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