제출 #1153477

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1153477		MPG	Commuter Pass (JOI18_commuter_pass)	C++20	100 / 100	321 ms	36424 KiB

commuter_pass

//#pragma GCC optomize("Ofast")
//#pragma GCC optimize("unroll-loops")
//#pragma GCC optimize("O3")
//#pragma GCC target("avx2")
//#pragma GCC target("sse,sse2,sse4.1,sse4.2") 



#include <bits/stdc++.h>
using namespace std;
typedef long long                           ll;
#define                                     max_heap priority_queue<pair <ll, pair <ll, ll>>>
#define                                     min_heap priority_queue<pair <ll, ll>, vector<pair <ll, ll>>, greater<pair <ll, ll>>>
//#define                                     min_heap priority_queue<ll, vector<ll>, greater<ll>>
#define                                     sariE cin.tie(NULL); cout.tie(NULL); ios_base::sync_with_stdio(false);
#define                                     filE freopen("in.txt", "r", stdin); freopen("out1.txt", "w", stdout); 
#define                                     endl '\n'
#define                                     md(a) (a % mod + mod) % mod
#define pb push_back
//cout << vectorprecision(5) << fixed << f;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

ll const maxn = 2e5 + 123;
ll const inf = 2e18;
ll const loG = 23;
//ll const mod = 1e9 + 7;
ll const mod = 998244353;
ll const sq = 350;
ll power(ll a, ll b, ll mod){if(b==0)return 1;if(b==1)return a;ll x = power(a, b / 2, mod);return (((x * x) % mod) * (b % 2 ? a : 1)) % mod;}


ll n, m, s, t, uu, vv, disu[maxn], disv[maxn], jell[maxn], posh[maxn];
bool mark[maxn];
vector <pair <ll, ll>> g[maxn];
vector <ll> par[maxn], child[maxn];


void djk(ll v, ll dis[maxn]){
    for (int i = 1; i < n + 1; i++){
        dis[i] = inf;
        mark[i] = 0;
    }
    dis[v] = 0;
    min_heap qu; qu.push({0, v});
    while (qu.size()){
        v = qu.top().second; qu.pop();
        if (mark[v])
            continue;
        mark[v] = 1;
        for (auto u : g[v]){
            if (!mark[u.first] && dis[u.first] > dis[v] + u.second){
                dis[u.first] = dis[v] + u.second;
                qu.push({dis[u.first], u.first});
            }
        }
    }
}

void babayab(ll v){
    ll dis[maxn];
    for (int i = 1; i < n + 1; i++){
        dis[i] = inf;
    }
    dis[v] = 0;
    min_heap qu; qu.push({0, v});
    while (qu.size()){
        v = qu.top().second; qu.pop();
        for (auto u : g[v]){
            if (dis[u.first] > dis[v] + u.second){
                dis[u.first] = dis[v] + u.second;
                par[u.first].clear(); par[u.first].push_back(v);
                qu.push({dis[u.first], u.first});
            }
            else if (dis[u.first] == dis[v] + u.second){
                par[u.first].push_back(v);
            }
        }
    }
}

void bache(ll v){
    for (int i = 1; i < n + 1; i++)
        mark[i] = 0;
    queue <ll> qu; qu.push(v);
    while (qu.size()){
        v = qu.front(); qu.pop();
        if (mark[v])
            continue;
        mark[v] = 1;
        for (ll u : par[v]){
            qu.push(u);
            child[u].push_back(v);
        }
    }
}


ll getjell(ll v){
    if (jell[v] != -1)
        return jell[v];
    ll ret = disv[v];
    for (ll u : child[v]){
        ret = min(ret, getjell(u));
    }
    jell[v] = ret;
    return ret;
}


ll getposh(ll v){
    if (posh[v] != -1)
        return posh[v];
    ll ret = disv[v];
    for (ll u : par[v]){
        ret = min(ret, getposh(u));
    }
    posh[v] = ret;
    return ret;
}



void Solve(){

cin >> n >> m >> s >> t >> uu >> vv;
for (int i = 1; i < m + 1; i++){
    ll a, b, c; cin >> a >> b >> c;
    g[a].push_back({b, c});
    g[b].push_back({a, c});
}
djk(uu, disu);
djk(vv, disv);
babayab(s);
bache(t);
for (int i = 1; i < n + 1; i++){
    jell[i] = -1;
    posh[i] = -1;
}
ll ans = disu[vv];
for (int i = 1; i < n + 1; i++){
    if (mark[i])
        ans = min(ans, disu[i] + min(getjell(i), getposh(i)));
}
cout << ans << endl;


}



int main(){
sariE;// filE;



int test = 1;
//cin >> test;
while (test--) Solve();
return 0;
}

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