Submission #929267

#	Time	Username	Problem	Language	Result	Execution time	Memory
929267		ono_de206	Airplane (NOI23_airplane)	C++14	100 / 100	438 ms	38440 KiB

Main

#include<bits/stdc++.h>
using namespace std;

#define fast ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define in insert
#define all(x) x.begin(),x.end()
#define pb push_back
#define eb emplace_back
#define ff first
#define ss second

#define int long long

typedef long long ll;
typedef vector<int> vi;
typedef set<int> si;
typedef multiset<int> msi;
typedef pair<int, int> pii;
typedef vector<pii> vpii;
// typedef pair<int, int> P;

template<typename T, typename U>
ostream & operator << (ostream &out, const pair<T, U> &c) {
	out << c.first << ' ' << c.second;
	return out;
}

template<typename T>
ostream & operator << (ostream &out, vector<T> &v) {
	const int sz = v.size();
	for (int i = 0; i < sz; i++) {
		if (i) out << ' ';
		out << v[i];
	}
	return out;
}

template<typename T>
istream & operator >> (istream &in, vector<T> &v) {
	for (T &x : v) in >> x;
	return in;
}

template<typename T, typename U>
	istream & operator >> (istream &in, pair<T, U> &c) {
	in >> c.first;
	in >> c.second;
	return in;
}

template<typename T>
void mxx(T &a, T b){if(b > a) a = b;}
template<typename T>
void mnn(T &a, T b){if(b < a) a = b;}

const int mxn = 2e5 + 10, MXLOG = 22, mod = 1e9 + 7, P = 1181, D = 1523, N = 2500;
const long long inf = 2e18 + 10;
int a[mxn], n;
vector<int> g[mxn];

vector<pair<int, int>> bfs(int st) {
	vector<pair<int, int>> ret(n + 1, make_pair(inf, inf));
	ret[st] = make_pair(0, a[st]);
	priority_queue<pair<pair<int, int>, int>, vector<pair<pair<int, int>, int>>, greater<pair<pair<int, int>, int>>> q;
	q.emplace(ret[st], st);
	while(q.size()) {
		auto my = q.top().ff;
		int x = q.top().ss;
		q.pop();
		if(my != ret[x]) continue;
		for(int y : g[x]) {
			auto nxt = my;
			mxx(nxt.ss, a[y]);
			nxt.ff = max(a[y], nxt.ff + 1);
			if(nxt < ret[y]) {
				ret[y] = nxt;
				q.emplace(ret[y], y);
			}
		}
	}
	return ret;
}

void go() {
	int m;
	cin >> n >> m;
	for(int i = 1; i <= n; i++) {
		cin >> a[i];
	}
	for(int i = 1; i <= m; i++) {
		int x, y;
		cin >> x >> y;
		g[x].pb(y);
		g[y].pb(x);
	}
	auto d1 = bfs(1);
	auto d2 = bfs(n);
	int ans = inf;
	for(int i = 1; i <= n; i++) {
		if(d1[i].ss == a[i] && d2[i].ss == a[i]) mnn(ans, d1[i].ff + d2[i].ff);
	}
	cout << ans << endl;
}

signed main() {
	fast;
	int t = 1;
	// cin >> t;
	while(t--) {
		go();
	}
	return 0;
}

• Subtask 1: 22 / 22
• Subtask 2: 10 / 10
• Subtask 3: 31 / 31
• Subtask 4: 37 / 37