Submission #329305

#	Time	Username	Problem	Language	Result	Execution time	Memory
329305		HoneyBadger	Commuter Pass (JOI18_commuter_pass)	C++17	24 / 100	2080 ms	49016 KiB

commuter_pass

#include <iostream>
#include <iomanip>
#include <cstdio>
#include <vector>
#include <bitset>
#include <string>
#include <cstring>
#include <map>
#include <set>
#include <stack>
#include <queue>
#include <deque>
#include <utility>
#include <algorithm>
#include <random>
#include <cmath>
#include <cassert>
#include <climits>
#include <ctime>
#include <chrono>


/*
#pragma GCC optimize("Ofast")
#pragma GCC optimize("O3")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,sse4.1,sse4.2,popcnt,abm,mmx,avx,avx2,tune=native")
*/


#ifdef LOCAL
    #define dbg(x) cout << #x << " : " << x << endl;
#else
    #define dbg(x)
#endif

#define int long long
#define pb push_back
#define ppb pop_back()
#define mp make_pair
#define fi(a, b) for (int i = a; i < b; i++)
#define fj(a, b) for (int j = a; j < b; j++)
#define fk(a, b) for (int k = a; k < b; k++)
#define fi1(a, b) for (int i = a - 1; i >= b; i--)
#define fj1(a, b) for (int j = a - 1; j >= b; j--)
#define fk1(a, b) for (int k = a - 1; k >= b; k--)
#define fx(x, a) for (auto& x : a)
#define rep(i, a, b) for (int i = a; i < b; ++i)
#define rep1(i, a, b) for (int i = a - 1; i >= b; --i)
#define siz(x) (int)x.size()
#define lb lower_bound
#define ub upper_bound
#define all(x) x.begin(), x.end()

using namespace std;

template<typename T1, typename T2>inline void mine(T1 &x, const T2 &y) { if (y < x) x = y; }
template<typename T1, typename T2>inline void maxe(T1 &x, const T2 &y) { if (x < y) x = y; }

ostream& operator << (ostream &out, const vector<int> &b) {
    for (auto k : b) out << k << ' ';
    return out;
}

typedef long long ll;
typedef unsigned long long ull;
typedef long double ld;
typedef char ch;
typedef string str;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<pii> vpii;
typedef vector<vpii> vvpii;
typedef vector<ch> vch;
typedef vector<vch> vvch;
typedef vector<str> vs;



const int MOD = 1000000007;
const int INF = 1000000050;
const long long BIG = (long long)2e18 + 50;
const int MX = 200010;
const double EPS = 1e-9;


mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

int n;
vpii g[MX];

vi dij(int s) {
	vi dist(n, BIG);
	dist[s] = 0;
	priority_queue<pii> q;
	q.push({s, 0});
	while (q.size()) {
		auto[v, dv] = q.top();
		dv *= -1;
		q.pop();
		if (dv > dist[v]) continue;
		for (auto[to, c] : g[v]) {
			if (dist[to] > dv + c) {
				dist[to] = dv + c;
				q.push({to, -dist[to]});
			}
		}
	}
	return dist;
}

int32_t main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int m, s, t, u, v;
    cin >> n >> m >> s >> t >> u >> v;
    --s, --t, --u, --v;
    while (m--) {
    	int a, b, c;
    	cin >> a >> b >> c;
    	--a, --b;
    	g[a].pb({b, c});
    	g[b].pb({a, c}); 
    }
   	vi ds = dij(s);
   	vi p(n);
   	fi(0, n) {
   		p[i] = i;
   	}
   	sort(all(p), [&](int a, int b){return ds[a] > ds[b];});
   	vch can(n, 0);
   	fx(x, p) {
   		can[x] = x == t;
   		for (auto[to, c] : g[x]) {
   			if (ds[x] + c == ds[to]) {
   				can[x] |= can[to];
   			}
   		}
   	}
   	vi dpu(n, BIG);
   	vi dpv(n, BIG);
   	vi du = dij(u);
   	vi dv = dij(v);
   	assert(du[v] == dv[u]);
   	assert(du[v] < BIG);
   	ll ans = du[v];
   	fx(x, p) {
   		if (!can[x]) continue;
   		//dbg(x);
		for (auto[to, c] : g[x]) {
			if (!can[to] || ds[x] + c != ds[to]) continue;
			mine(dpu[x], dpu[to]);
			mine(dpv[x], dpv[to]);
		}	
		mine(ans, dpu[x] + dv[x]);
		mine(ans, dpv[x] + du[x]);
		mine(dpu[x], du[x]);
		mine(dpv[x], dv[x]);
   	}
   	cout << ans << '\n';
}

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